A Factor Of Ten

We all know that if you want to make something big, you have to compose it out of components — modules of some sort.  You must be able to isolate parts. . . .  It’s well known from programming, that this is not just a matter of division of labor because if you choose the wrong interface or an inappropriate one, the work explodes by a factor of ten — it’s not just a sum.
—    Edsger W. Dijkstra
[Dijkstra doesn’t mention a “great” programmer is 10 times more productive (BY ANY MEASURE) than a “good” programmer, and good programmers can be 5 to 10 times more productive than “average” programmers.   —    kmab]
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