26 KiB
26 KiB
Quality House
Visual rendering of qfd.md — the same 13 WHATs × 15 HOWs as a
classical House of Quality. The roof carries function-vs-function
correlations from §4; the basement carries v0.1 targets (§2) plus the
weighted-vote sums and relative weights from §3.
qfd.md is authoritative — this file lags it. Regenerate when the matrix
or roof changes; if numbers diverge, trust qfd.md.
Out of scope here: §5 component mapping (would need a second house), §6 critical performance budget (already a curated rank), §7 tradeoffs (narrative), §8 inconsistencies (history).
The perception zone scores four products against the WHATs on a 0–5 scale. These are educated guesses, not measurements — see the scoring rationale below for what each cell is based on. Useful for self-positioning ("where do we land vs the market"), not as a fair head-to-head buyer's guide.
% =====================================================================
% QFD "House of Quality" preamble
% =====================================================================
\usetikzlibrary{arrows.meta, positioning, shapes.geometric, shapes.misc, calc, fit, backgrounds}
\newif\ifqfdshowroof \qfdshowrooftrue
\newif\ifqfdshowbasement \qfdshowbasementtrue
\newif\ifqfdshowcompetitive \qfdshowcompetitivetrue
\newif\ifqfdshowlegend \qfdshowlegendtrue
\newif\ifqfdshowimportance \qfdshowimportancetrue
\newif\ifqfdshowcorrlegend \qfdshowcorrlegendtrue
\newif\ifqfdshowevallegend \qfdshowevallegendtrue
\def\qfdNW{5}
\def\qfdNH{5}
\def\qfdWhatW{4.0}
\def\qfdImpW{0.9}
\def\qfdCmpW{3}
\def\qfdHdrH{2.6}
\def\qfdBasementN{4}
\def\qfdWhatsTitle{Customer needs}
\def\qfdImpTitle{Imp.\ \%}
\def\qfdPerceptionTitle{Comparative evaluation}
\def\qfdPoorLabel{poor}
\def\qfdExcellentLabel{excellent}
\def\qfdAltOneLabel{Our product}
\def\qfdAltTwoLabel{Competitor A}
\def\qfdAltThreeLabel{Competitor B}
\def\qfdRelTitle{Relation}
\def\qfdCorrTitle{Correlation}
\def\qfdEvalTitle{Evaluation}
\tikzset{
qfdthin/.style ={line width=0.35pt},
qfdmed/.style ={line width=0.7pt},
qfdstrong/.style={circle, draw, fill=black,
minimum size=7pt, inner sep=0pt},
qfdmod/.style ={circle, draw,
minimum size=7pt, inner sep=0pt, line width=0.8pt},
qfdweak/.style ={regular polygon, regular polygon sides=3, draw,
minimum size=8.5pt, inner sep=0pt, line width=0.7pt},
qfdrel/.is choice,
qfdrel/S/.style={qfdstrong},
qfdrel/M/.style={qfdmod},
qfdrel/W/.style={qfdweak},
qfdalt1mk/.style={circle, draw, fill=black,
minimum size=6pt, inner sep=0pt, line width=1pt},
qfdalt1ln/.style={line width=1.2pt},
qfdalt2mk/.style={regular polygon, regular polygon sides=3, draw,
fill=black, minimum size=6pt, inner sep=0pt,
line width=0.7pt},
qfdalt2ln/.style={line width=0.7pt, dashed},
qfdalt3mk/.style={rectangle, draw, fill=black,
minimum size=5pt, inner sep=0pt, line width=0.7pt},
qfdalt3ln/.style={line width=0.7pt, dotted},
}
\newcommand{\qfdDrawGrid}{%
\foreach \c in {1,...,\qfdNHm} \draw[qfdthin] (\c, 0) -- (\c, -\qfdNW);
\foreach \r in {1,...,\qfdNWm} \draw[qfdthin] (0, -\r) -- (\qfdNH, -\r);
\foreach \r in {1,...,\qfdNWm}
\draw[qfdthin] (\qfdLeftEdge, -\r) -- (0, -\r);
\ifqfdshowroof
\foreach \c in {1,...,\qfdNHm}
\draw[qfdthin] (\c, 0) -- (\c, \qfdHdrH);
\fi
\ifqfdshowcompetitive
\foreach \r in {1,...,\qfdNWm}
\draw[qfdthin] (\qfdNH, -\r) -- (\qfdNH+\qfdCmpW, -\r);
\fi
\ifqfdshowbasement
\foreach \r in {1,...,\qfdBasementN}
\draw[qfdthin] (0, -\qfdNW-\r) -- (\qfdNH, -\qfdNW-\r);
\foreach \c in {1,...,\qfdNHm}
\draw[qfdthin] (\c, -\qfdNW) -- (\c, -\qfdNW-\qfdBasementN);
\fi
}
\newcommand{\qfdDrawRoof}{%
\ifqfdshowroof
\foreach \k in {1,...,\qfdNHm} {%
\pgfmathsetmacro{\rx}{(\k+\qfdNH)/2}
\pgfmathsetmacro{\ry}{\qfdHdrH + (\qfdNH-\k)/2}
\pgfmathsetmacro{\lx}{\k/2}
\pgfmathsetmacro{\ly}{\qfdHdrH + \k/2}
\draw[qfdthin] (\k, \qfdHdrH) -- (\rx, \ry);
\draw[qfdthin] (\k, \qfdHdrH) -- (\lx, \ly);
}%
\draw[qfdmed] (0, \qfdHdrH)
-- (\qfdNH/2, \qfdApexY) -- (\qfdNH, \qfdHdrH);
\foreach \i in {1,...,\qfdNH}
\foreach \k in {1,...,\qfdNH} {%
\pgfmathtruncatemacro{\jj}{\i+\k}
\ifnum\jj>\qfdNH\relax\else
\pgfmathsetmacro{\xx}{\i + \k/2 - 0.5}
\pgfmathsetmacro{\yy}{\qfdHdrH + \k/2}
\coordinate (C-\i-\jj) at (\xx, \yy);
\fi
}%
\fi
}
\newcommand{\qfdDrawScale}{%
\ifqfdshowcompetitive
\foreach \tk in {0,1,2,3,4,5} {%
\pgfmathsetmacro{\tx}{\qfdNH + (\tk+0.5)*\qfdCmpW/6}
\node[anchor=south, font=\scriptsize] at (\tx, 0.02) {\tk};
}%
\node[anchor=south, font=\scriptsize\bfseries, align=center]
at ({\qfdNH + \qfdCmpW/2}, 0.7) {\qfdPerceptionTitle};
\node[anchor=north, font=\scriptsize\itshape]
at ({\qfdNH + 0.45}, -\qfdNW) {\qfdPoorLabel};
\node[anchor=north, font=\scriptsize\itshape]
at ({\qfdNH + \qfdCmpW - 0.45}, -\qfdNW) {\qfdExcellentLabel};
\fi
}
\newcommand{\qfdDrawZoneTitles}{%
\ifqfdshowimportance
\node[rotate=90, anchor=west, font=\footnotesize\bfseries]
at ({-\qfdImpW/2}, 0.12) {\qfdImpTitle};
\fi
\node[font=\scriptsize\bfseries, align=center, text width=\qfdWhatW cm]
at ({\qfdLeftEdge + \qfdWhatW/2},
{\ifqfdshowroof \qfdHdrH/2 \else 0.6 \fi}) {\qfdWhatsTitle};
}
\newcommand{\qfdDrawFrames}{%
\begin{scope}[qfdmed]
\draw (\qfdLeftEdge, 0) rectangle (\qfdNH, -\qfdNW);
\ifqfdshowimportance \draw (-\qfdImpW, 0) -- (-\qfdImpW, -\qfdNW); \fi
\draw (0, 0) -- (0, -\qfdNW);
\ifqfdshowroof
\draw (0, 0) rectangle (\qfdNH, \qfdHdrH); \fi
\ifqfdshowbasement
\draw (0, -\qfdNW) rectangle (\qfdNH, -\qfdNW-\qfdBasementN); \fi
\ifqfdshowcompetitive
\draw (\qfdNH, 0) rectangle (\qfdNH+\qfdCmpW, -\qfdNW); \fi
\end{scope}
}
\newcommand{\qfdDrawLegend}{%
\ifqfdshowlegend
\pgfmathsetmacro{\qfdLegX}{%
\qfdNH + \ifqfdshowcompetitive \qfdCmpW + 0.7 \else 0.7 \fi}
\pgfmathsetmacro{\qfdLegBottom}{%
-2.05
\ifqfdshowroof \ifqfdshowcorrlegend - 2.55 \fi \fi
\ifqfdshowcompetitive \ifqfdshowevallegend - 2.20 \fi \fi}
\pgfmathsetmacro{\qfdLegY}{\qfdHdrH - 0.4}
\begin{scope}[shift={(\qfdLegX, \qfdLegY)}]
\draw[qfdmed, rounded corners=2pt]
(-0.15, 0.4) rectangle (4.5, \qfdLegBottom);
\node[anchor=west, font=\footnotesize\bfseries] at (0, 0.1)
{\qfdRelTitle};
\draw[qfdthin] (0, -0.15) -- (4.35, -0.15);
\node[qfdstrong] at (0.22, -0.5) {};
\node[anchor=west] at (0.5, -0.5) {Strong (9)};
\node[qfdmod] at (0.22, -0.95) {};
\node[anchor=west] at (0.5, -0.95) {Medium (3)};
\node[qfdweak] at (0.22, -1.4) {};
\node[anchor=west] at (0.5, -1.4) {Weak (1)};
\ifqfdshowroof \ifqfdshowcorrlegend
\node[anchor=west, font=\footnotesize\bfseries] at (0, -2.10)
{\qfdCorrTitle};
\draw[qfdthin] (0, -2.35) -- (4.35, -2.35);
\node[anchor=west] at (0, -2.70) {{$+\!+$}\quad very positive};
\node[anchor=west] at (0, -3.05) {{$+$\phantom{$+$}}\quad positive};
\node[anchor=west] at (0, -3.40) {{$-$\phantom{$-$}}\quad negative};
\node[anchor=west] at (0, -3.75) {{$-\!-$}\quad very negative};
\fi \fi
\ifqfdshowcompetitive \ifqfdshowevallegend
\pgfmathsetmacro{\qfdEvalTop}{%
-2.10 \ifqfdshowroof\ifqfdshowcorrlegend - 2.55 \fi\fi}
\node[anchor=west, font=\footnotesize\bfseries]
at (0, \qfdEvalTop) {\qfdEvalTitle};
\pgfmathsetmacro{\qfdEvalSep}{\qfdEvalTop - 0.25}
\draw[qfdthin] (0, \qfdEvalSep) -- (4.35, \qfdEvalSep);
\pgfmathsetmacro{\qfdLegA}{\qfdEvalTop - 0.55}
\draw[qfdalt1ln] (0.05, \qfdLegA) -- (0.45, \qfdLegA);
\node[qfdalt1mk] at (0.25, \qfdLegA) {};
\node[anchor=west, font=\bfseries] at (0.55, \qfdLegA)
{\qfdAltOneLabel};
\pgfmathsetmacro{\qfdLegB}{\qfdEvalTop - 0.95}
\draw[qfdalt2ln] (0.05, \qfdLegB) -- (0.45, \qfdLegB);
\node[qfdalt2mk] at (0.25, \qfdLegB) {};
\node[anchor=west] at (0.55, \qfdLegB) {\qfdAltTwoLabel};
\pgfmathsetmacro{\qfdLegC}{\qfdEvalTop - 1.35}
\draw[qfdalt3ln] (0.05, \qfdLegC) -- (0.45, \qfdLegC);
\node[qfdalt3mk] at (0.25, \qfdLegC) {};
\node[anchor=west] at (0.55, \qfdLegC) {\qfdAltThreeLabel};
\fi \fi
\end{scope}
\fi
}
\newenvironment{qfdhouse}{%
\begin{tikzpicture}[x=1cm, y=1cm, font=\scriptsize,
line cap=round, line join=round]
\ifqfdshowimportance
\pgfmathsetmacro{\qfdLeftEdge}{-\qfdWhatW-\qfdImpW}
\else
\pgfmathsetmacro{\qfdLeftEdge}{-\qfdWhatW}
\fi
\pgfmathsetmacro{\qfdApexY}{\qfdHdrH + \qfdNH/2}
\pgfmathtruncatemacro{\qfdNHm}{\qfdNH - 1}
\pgfmathtruncatemacro{\qfdNWm}{\qfdNW - 1}
\qfdDrawGrid
\qfdDrawRoof
\qfdDrawScale
\qfdDrawZoneTitles
}{%
\qfdDrawFrames
\qfdDrawLegend
\end{tikzpicture}%
}
% --- Dimensions tuned for the typewriter QFD (13 W x 15 H) ---
\def\qfdNW{13}
\def\qfdNH{15}
\def\qfdWhatW{4.6}
\def\qfdImpW{0.7}
\def\qfdHdrH{3.2}
\def\qfdBasementN{3}
\def\qfdCmpW{3.4}
\qfdshowlegendfalse % we draw a 4-alternative legend manually
\def\qfdWhatsTitle{User-facing requirements (W)}
\def\qfdImpTitle{Weight}
\def\qfdPerceptionTitle{Competitive perception (0–5, guessed)}
\def\qfdPoorLabel{poor}
\def\qfdExcellentLabel{excellent}
% Perception-zone markers: shape + colour-blind-safe colour per product.
% Palette is Okabe-Ito (blue, vermillion, bluish green, reddish purple).
% Light fills + saturated outlines keep stacked markers legible.
\definecolor{qfdcOurs}{RGB}{0,114,178}
\definecolor{qfdcRem}{RGB}{213,94,0}
\definecolor{qfdcFrw}{RGB}{0,158,115}
\definecolor{qfdcPom}{RGB}{204,121,167}
\tikzset{
qfdalt1mk/.style={circle, draw=qfdcOurs, fill=qfdcOurs!55!white,
minimum size=6.5pt, inner sep=0pt, line width=1.1pt},
qfdalt1ln/.style={line width=1.2pt, qfdcOurs},
qfdalt2mk/.style={regular polygon, regular polygon sides=3,
draw=qfdcRem, fill=qfdcRem!55!white,
minimum size=7pt, inner sep=0pt, line width=0.9pt},
qfdalt2ln/.style={line width=0.8pt, dashed, qfdcRem},
qfdalt3mk/.style={rectangle, draw=qfdcFrw, fill=qfdcFrw!55!white,
minimum size=5.5pt, inner sep=0pt, line width=0.9pt},
qfdalt3ln/.style={line width=0.8pt, dotted, qfdcFrw},
qfdalt4mk/.style={diamond, aspect=1, draw=qfdcPom,
fill=qfdcPom!50!white,
minimum size=7pt, inner sep=0pt, line width=1.0pt},
qfdalt4ln/.style={line width=0.8pt, dash dot, qfdcPom},
}
\begin{document}
\begin{qfdhouse}
% ---------- WHATs (left column) ----------
\foreach \r/\t in {%
1/{W1 Sub-second visible response to typing},
2/{W2 Publishing is one deliberate action away},
3/{W3 Pulling power never corrupts the file},
4/{W4 Provisioning never interrupts a writing session},
5/{W5 Quick boot to a writing cursor},
6/{W6 Long sessions without crash, lag, drift},
7/{W7 Nothing on the device competes with prose},
8/{W8 The UI never moves except when I move it},
9/{W9 Codebase absorbs the planned roadmap},
10/{W10 I can repair or fork it with hobbyist tools},
11/{W11 Multi-day battery life (v0.8 onward)},
12/{W12 Local-only files coexist with git scope (v0.5+)},
13/{W13 Typography sets a writing-tool tone}%
}
\node[anchor=west, font=\scriptsize, text width=\qfdWhatW cm,
align=left]
at ({\qfdLeftEdge + 0.1}, {-\r + 0.5}) {\t};
% ---------- Importance (raw 1-10 weight) ----------
\foreach \r/\w in {1/10, 2/9, 3/10, 4/7, 5/6, 6/9, 7/8, 8/7,
9/8, 10/5, 11/4, 12/5, 13/7}
\node[font=\scriptsize] at ({-\qfdImpW/2}, {-\r + 0.5}) {\w};
% ---------- HOWs (rotated column titles) ----------
\foreach \c/\t in {%
1/{H1 Keypress$\to$glyph latency},
2/{H2 Refresh area per keystroke},
3/{H3 Full-refresh cadence},
4/{H4 Cold boot to cursor},
5/{H5 Continuous-typing endurance},
6/{H6 Push success rate},
7/{H7 Push end-to-end time},
8/{H8 Save durability vs power loss},
9/{H9 PSRAM heap headroom},
10/{H10 Firmware binary size},
11/{H11 Total stack budget},
12/{H12 Wi-Fi reconnect time},
13/{H13 Idle / typing / push current},
14/{H14 Module / API surface count},
15/{H15 Clean release build time}%
}
\node[rotate=90, anchor=west, font=\scriptsize]
at ({\c - 0.5}, 0.15) {\t};
% ---------- Relation matrix (S=9, M=3, W=1) ----------
% W1 row 1: H1S H2S H3M H5M H9W H11W
\node[qfdrel/S] at ({1 - 0.5}, {-1 + 0.5}) {};
\node[qfdrel/S] at ({2 - 0.5}, {-1 + 0.5}) {};
\node[qfdrel/M] at ({3 - 0.5}, {-1 + 0.5}) {};
\node[qfdrel/M] at ({5 - 0.5}, {-1 + 0.5}) {};
\node[qfdrel/W] at ({9 - 0.5}, {-1 + 0.5}) {};
\node[qfdrel/W] at ({11 - 0.5}, {-1 + 0.5}) {};
% W2 row 2: H6S H7M H9S H12S
\node[qfdrel/S] at ({6 - 0.5}, {-2 + 0.5}) {};
\node[qfdrel/M] at ({7 - 0.5}, {-2 + 0.5}) {};
\node[qfdrel/S] at ({9 - 0.5}, {-2 + 0.5}) {};
\node[qfdrel/S] at ({12 - 0.5}, {-2 + 0.5}) {};
% W3 row 3: H8S
\node[qfdrel/S] at ({8 - 0.5}, {-3 + 0.5}) {};
% W4 row 4: H6M H12M H14W
\node[qfdrel/M] at ({6 - 0.5}, {-4 + 0.5}) {};
\node[qfdrel/M] at ({12 - 0.5}, {-4 + 0.5}) {};
\node[qfdrel/W] at ({14 - 0.5}, {-4 + 0.5}) {};
% W5 row 5: H4S H10M
\node[qfdrel/S] at ({4 - 0.5}, {-5 + 0.5}) {};
\node[qfdrel/M] at ({10 - 0.5}, {-5 + 0.5}) {};
% W6 row 6: H1M H3M H5S H6M H8M H9S H11M H12M
\node[qfdrel/M] at ({1 - 0.5}, {-6 + 0.5}) {};
\node[qfdrel/M] at ({3 - 0.5}, {-6 + 0.5}) {};
\node[qfdrel/S] at ({5 - 0.5}, {-6 + 0.5}) {};
\node[qfdrel/M] at ({6 - 0.5}, {-6 + 0.5}) {};
\node[qfdrel/M] at ({8 - 0.5}, {-6 + 0.5}) {};
\node[qfdrel/S] at ({9 - 0.5}, {-6 + 0.5}) {};
\node[qfdrel/M] at ({11 - 0.5}, {-6 + 0.5}) {};
\node[qfdrel/M] at ({12 - 0.5}, {-6 + 0.5}) {};
% W7 row 7: H1M H2M H3M H13M H14W
\node[qfdrel/M] at ({1 - 0.5}, {-7 + 0.5}) {};
\node[qfdrel/M] at ({2 - 0.5}, {-7 + 0.5}) {};
\node[qfdrel/M] at ({3 - 0.5}, {-7 + 0.5}) {};
\node[qfdrel/M] at ({13 - 0.5}, {-7 + 0.5}) {};
\node[qfdrel/W] at ({14 - 0.5}, {-7 + 0.5}) {};
% W8 row 8: H1W H2S H3S
\node[qfdrel/W] at ({1 - 0.5}, {-8 + 0.5}) {};
\node[qfdrel/S] at ({2 - 0.5}, {-8 + 0.5}) {};
\node[qfdrel/S] at ({3 - 0.5}, {-8 + 0.5}) {};
% W9 row 9: H10W H11W H14S H15M
\node[qfdrel/W] at ({10 - 0.5}, {-9 + 0.5}) {};
\node[qfdrel/W] at ({11 - 0.5}, {-9 + 0.5}) {};
\node[qfdrel/S] at ({14 - 0.5}, {-9 + 0.5}) {};
\node[qfdrel/M] at ({15 - 0.5}, {-9 + 0.5}) {};
% W10 row 10: H10M H13W H14M H15W
\node[qfdrel/M] at ({10 - 0.5}, {-10 + 0.5}) {};
\node[qfdrel/W] at ({13 - 0.5}, {-10 + 0.5}) {};
\node[qfdrel/M] at ({14 - 0.5}, {-10 + 0.5}) {};
\node[qfdrel/W] at ({15 - 0.5}, {-10 + 0.5}) {};
% W11 row 11: H13S
\node[qfdrel/S] at ({13 - 0.5}, {-11 + 0.5}) {};
% W12 row 12: H6W H8M H14M
\node[qfdrel/W] at ({6 - 0.5}, {-12 + 0.5}) {};
\node[qfdrel/M] at ({8 - 0.5}, {-12 + 0.5}) {};
\node[qfdrel/M] at ({14 - 0.5}, {-12 + 0.5}) {};
% W13 row 13: H9M
\node[qfdrel/M] at ({9 - 0.5}, {-13 + 0.5}) {};
% ---------- Roof correlations ----------
\node[font=\scriptsize] at (C-1-2) {$+\!+$}; % H1-H2 strong reinforce
\node[font=\scriptsize] at (C-1-3) {$-$}; % H1-H3 mild conflict
\node[font=\scriptsize] at (C-1-5) {$+$}; % H1-H5 mild reinforce
\node[font=\scriptsize] at (C-1-13) {$-$}; % H1-H13 mild conflict
\node[font=\scriptsize] at (C-2-3) {$+\!+$}; % H2-H3 strong reinforce
\node[font=\scriptsize] at (C-2-13) {$+$}; % H2-H13
\node[font=\scriptsize] at (C-3-13) {$+$}; % H3-H13
\node[font=\scriptsize] at (C-4-10) {$-$}; % H4-H10 boot vs binary
\node[font=\scriptsize] at (C-5-6) {$+$}; % H5-H6
\node[font=\scriptsize] at (C-5-8) {$+$}; % H5-H8
\node[font=\scriptsize] at (C-5-9) {$-\!-$}; % H5-H9 soak vs heap
\node[font=\scriptsize] at (C-6-7) {$+$}; % H6-H7
\node[font=\scriptsize] at (C-6-9) {$-\!-$}; % H6-H9 push vs heap
\node[font=\scriptsize] at (C-6-12) {$+\!+$}; % H6-H12
\node[font=\scriptsize] at (C-7-9) {$-$}; % H7-H9
\node[font=\scriptsize] at (C-7-12) {$+\!+$}; % H7-H12
\node[font=\scriptsize] at (C-9-10) {$-\!-$}; % H9-H10 heap vs binary
\node[font=\scriptsize] at (C-10-15) {$-\!-$}; % H10-H15 binary vs build
\node[font=\scriptsize] at (C-11-13) {$-$}; % H11-H13
\node[font=\scriptsize] at (C-14-15) {$-$}; % H14-H15 modularity vs build
% ---------- Basement: target / abs weight / rel weight % ----------
\foreach \c/\tgt/\abs/\rel in {%
1/{$\leq$200\,ms}/148/10,
2/{$\leq$1 line}/177/11,
3/{1 : 20}/144/9,
4/{$\leq$5\,s}/54/3,
5/{$\geq$1\,h}/111/7,
6/{$\geq$95\,\%}/134/9,
7/{$\leq$30\,s}/27/2,
8/{100\,\%}/132/9,
9/{$\geq$1\,MB}/193/12,
10/{$\leq$2\,MB}/41/3,
11/{$\leq$80\,KB}/45/3,
12/{$\leq$30\,s}/129/8,
13/{obs.}/65/4,
14/{$\leq$8}/117/8,
15/{$\leq$7\,min}/29/2%
} {
\node[font=\scriptsize] at ({\c - 0.5}, {-\qfdNW - 0.5}) {\tgt};
\node[font=\scriptsize] at ({\c - 0.5}, {-\qfdNW - 1.5}) {\abs};
\node[font=\scriptsize\bfseries]
at ({\c - 0.5}, {-\qfdNW - 2.5}) {\rel};
}
% ---------- Basement row labels (in the margin below WHATs) ----------
\foreach \k/\lbl in {1/{Target (v0.1)}, 2/{$\Sigma$ abs}, 3/{Rel.\ \%}}
\node[anchor=east, font=\scriptsize\itshape]
at ({-0.1}, {-\qfdNW - \k + 0.5}) {\lbl};
% ---------- Perception zone: 4 products x 13 WHATs (0-5 scores) ----------
% Columns: \so=Ours target, \st=reMarkable 2 + Type Folio,
% \sf=Freewrite Traveler, \sg=Pomera DM250.
\foreach \r/\so/\st/\sf/\sg in {%
1/4/3/3/5,
2/5/4/4/2,
3/4/4/2/2,
4/5/2/2/5,
5/4/3/3/5,
6/3/3/4/5,
7/5/2/5/5,
8/4/3/4/5,
9/4/3/1/1,
10/5/4/2/1,
11/1/5/5/4,
12/3/1/2/3,
13/3/5/2/2%
} {
\pgfmathsetmacro{\xo}{\qfdNH + (\so + 0.5)*\qfdCmpW/6}
\pgfmathsetmacro{\xt}{\qfdNH + (\st + 0.5)*\qfdCmpW/6}
\pgfmathsetmacro{\xf}{\qfdNH + (\sf + 0.5)*\qfdCmpW/6}
\pgfmathsetmacro{\xg}{\qfdNH + (\sg + 0.5)*\qfdCmpW/6}
\node[qfdalt1mk] at (\xo, {-\r + 0.5}) {};
\node[qfdalt2mk] at (\xt, {-\r + 0.5}) {};
\node[qfdalt3mk] at (\xf, {-\r + 0.5}) {};
\node[qfdalt4mk] at (\xg, {-\r + 0.5}) {};
}
% ---------- Manual legend (4 alternatives, placed right of zones) ----------
\pgfmathsetmacro{\qfdLegX}{\qfdNH + \qfdCmpW + 0.7}
\begin{scope}[shift={(\qfdLegX, \qfdHdrH - 0.4)}]
\draw[qfdmed, rounded corners=2pt]
(-0.15, 0.4) rectangle (5.1, -7.05);
% Relations
\node[anchor=west, font=\footnotesize\bfseries] at (0, 0.1)
{Relation};
\draw[qfdthin] (0, -0.15) -- (4.95, -0.15);
\node[qfdstrong] at (0.22, -0.5) {};
\node[anchor=west] at (0.5, -0.5) {Strong (9)};
\node[qfdmod] at (0.22, -0.95) {};
\node[anchor=west] at (0.5, -0.95) {Medium (3)};
\node[qfdweak] at (0.22, -1.4) {};
\node[anchor=west] at (0.5, -1.4) {Weak (1)};
% Correlation
\node[anchor=west, font=\footnotesize\bfseries] at (0, -2.10)
{Correlation};
\draw[qfdthin] (0, -2.35) -- (4.95, -2.35);
\node[anchor=west] at (0, -2.70) {{$+\!+$}\quad very positive};
\node[anchor=west] at (0, -3.05) {{$+$\phantom{$+$}}\quad positive};
\node[anchor=west] at (0, -3.40) {{$-$\phantom{$-$}}\quad negative};
\node[anchor=west] at (0, -3.75) {{$-\!-$}\quad very negative};
% Perception
\node[anchor=west, font=\footnotesize\bfseries] at (0, -4.20)
{Perception};
\draw[qfdthin] (0, -4.45) -- (4.95, -4.45);
\draw[qfdalt1ln] (0.05, -4.80) -- (0.45, -4.80);
\node[qfdalt1mk] at (0.25, -4.80) {};
\node[anchor=west, font=\bfseries] at (0.55, -4.80)
{Ours (v0.1 target)};
\draw[qfdalt2ln] (0.05, -5.25) -- (0.45, -5.25);
\node[qfdalt2mk] at (0.25, -5.25) {};
\node[anchor=west] at (0.55, -5.25) {reMarkable 2 + Type Folio};
\draw[qfdalt3ln] (0.05, -5.70) -- (0.45, -5.70);
\node[qfdalt3mk] at (0.25, -5.70) {};
\node[anchor=west] at (0.55, -5.70) {Freewrite Traveler};
\draw[qfdalt4ln] (0.05, -6.15) -- (0.45, -6.15);
\node[qfdalt4mk] at (0.25, -6.15) {};
\node[anchor=west] at (0.55, -6.15) {Pomera DM250};
\node[anchor=west, font=\scriptsize\itshape] at (0, -6.70)
{0 = poor, 5 = excellent};
\end{scope}
\end{qfdhouse}
\end{document}
Perception scores (guessed)
Four products on the 0–5 scale, scored against each WHAT. Reference
configurations: reMarkable 2 + Type Folio, Freewrite Traveler,
Pomera DM250 (DM250 has a reflective monochrome LCD, not e-ink — flagged
in W1 / W8). "Ours" is the v0.1 target from qfd.md §2, not measured yet.
| ID | WHAT (truncated) | Ours | reM. | Frw. | Pom. | Rationale (shortest defensible) |
|---|---|---|---|---|---|---|
| W1 | Sub-second response to typing | 4 | 3 | 3 | 5 | Ours targets ≤200 ms; reMarkable + Freewrite (e-ink) are visibly laggy; Pomera's reflective LCD is near-zero. |
| W2 | Publishing is one deliberate action away | 5 | 4 | 4 | 2 | Ctrl-G atomic; reMarkable + Freewrite cloud-sync is one-tap but not git; Pomera = USB/SD copy or QR transfer. |
| W3 | Pulling power never corrupts the file | 4 | 4 | 2 | 2 | Ours: atomic-rename + fsync. reMarkable journals. Freewrite + Pomera: forum reports of corruption on yank. |
| W4 | Provisioning never interrupts writing | 5 | 2 | 2 | 5 | Ours v0.1: build-time config (dev-only). reM/Frw need Wi-Fi + account. Pomera: literally none. |
| W5 | Quick boot to a writing cursor | 4 | 3 | 3 | 5 | Ours target ≤5 s. reMarkable cold-boots ~20 s (great from sleep). Pomera ~3 s. |
| W6 | Long sessions without crash / lag / drift | 3 | 3 | 4 | 5 | Ours unproven (1 h target). Freewrite famously stable. Pomera firmware is decades-mature. |
| W7 | Nothing on the device competes with prose | 5 | 2 | 5 | 5 | reMarkable has apps, menus, drawing, PDFs. Freewrite + Pomera are single-purpose; ours by design. |
| W8 | The UI never moves except when I move it | 4 | 3 | 4 | 5 | reMarkable animates more; ours uses dirty-rects; Freewrite minimal motion; Pomera near-static LCD. |
| W9 | Codebase absorbs the planned roadmap | 4 | 3 | 1 | 1 | Modular Rust ours; reMarkable is hackable Linux; Freewrite + Pomera are closed firmware. |
| W10 | I can repair or fork it with hobbyist tools | 5 | 4 | 2 | 1 | Ours: open BOM + ESP32. reMarkable: rooted Linux + community ROMs. Freewrite + Pomera: closed. |
| W11 | Multi-day battery life (v0.8 onward) | 1 | 5 | 5 | 4 | Ours v0.1 = wall-powered (battery deferred). reMarkable + Freewrite Traveler legendary. Pomera ~24 h. |
| W12 | Local-only files coexist with git scope | 3 | 1 | 2 | 3 | Ours v0.5+ design. reMarkable cloud-only. Freewrite has local + Postbox but no VCS. Pomera = pure local. |
| W13 | Typography sets a writing-tool tone | 3 | 5 | 2 | 2 | Ours v0.1: single mono (serif option in v1.0). reMarkable: rich type rendering. Freewrite + Pomera: utilitarian. |
Totals (sum across 13 WHATs, no weighting): Ours 50, Pomera 45,
reMarkable 42, Freewrite 39. Pomera ranking second is the useful signal —
we're effectively building "Pomera + Wi-Fi + git + hackable BOM", which
re-confirms the differentiation thesis from README.md.
Weighted totals (Σ score × W weight) tell the same story with more contrast — left as exercise; the unweighted view is enough to read the picture.
Caveats
- Single-rater bias. All thirteen rows are scored from the project author's POV. A reMarkable buyer would weight W11 (battery) at 10 and W12 (git) at 1, flipping the totals.
- Configuration matters. Freewrite Smart Typewriter (e-ink) scores differently from Traveler (LCD) on W1 / W5. The table picks Traveler as the most direct competitor.
- W3 / W6 Freewrite scores are anecdotal. Forum reports, not bench data. Treat the 2 / 4 as "we'd need to test this" rather than fact.
- No price column. Ours-as-BOM is materially cheaper than the
competitors but cost is not a WHAT in
qfd.md§1, so it's absent here. Worth a row if a v0.x WHAT ever calls it out.
Reading the house
- Importance (left column) is the raw 1–10 weight from
qfd.md§1, not a normalised %, so adding stays cheap when a WHAT shifts. Sum of weights is 95; treat each unit as ~1.05 % if you want a percentage view. - Roof carries the §4 symbols translated into classical QFD glyphs:
++strong reinforcement (◎),+mild reinforcement (○),−mild conflict (×),−−strong conflict (⊗). - Basement rows are: v0.1 target → §3 column sum (
Σofweight × strength) → relative weight as integer % of total (1546). Relative weights round to 100. - H7, H10, H15 (push time, binary size, build time) sit at the bottom
of the basement — knowingly-paid costs per
qfd.md§7, not signals to optimise harder.
Regenerating
When qfd.md §1–§4 change, re-derive:
- Importance column → §1 weight column.
- HOW titles + targets → §2 (v0.1 target column).
- Relation cells → §3 matrix strengths (9 →
S, 3 →M, 1 →W). - Roof symbols → §4 (◎→
++, ○→+, ×→−, ⊗→−−). - Basement Σ + Rel% → §3 bottom row, divided by the new total.
- Perception scores are not derived from
qfd.md— they live only in this file. Update them when (a) a competitor ships a relevant change, (b) measurement replaces a guess, or (c) a WHAT is added/removed in §1. Each score should keep its one-line rationale in the table above.
If a renderer rejects the tikz fence, the file is still readable as
source — the placement comments name each WHAT, HOW, and cell. The
perception-scores table above is the human-readable fallback for the
right-hand zone of the diagram.