[xorblurb]

I'd like to add my grain of salt here: I can agree about the don't rewrite from scratch "rule", but only depending on the context -- and also only when looking at all the details of a given project.

When bengoodger says "reacting to the complexity of the code", I doubt this is as messy as what can be found in some private codebase produced over a decade by some less-than-google-level employees who since left. So while the never-recode myth has some value in somehow (at least) good code bases, and depending on the angle of view (to even judge whether an approach constitute a rewrite or not), it also has a rather big cost, when some manager try to use it on projects far beyond the non-return point to justify forcing engineer to swim in the septic tank instead of doing any valuable work.

After all, for each Netscape (which BTW, involves a quite good amount of technical and commercial mix, and even then Mozilla is still with us today...) I could ask why a corresponding NT has not evolved from consumer Windows... (some parts were shared, but again: the angle of view...)

[jasim]

Not a counter-point at all, just an aside: consumer windows and NT were fundamentally different software. The "Showstopper! the Breakneck Race to Create Windows NT and the Next Generation at Microsoft" book is a packed guide of what happened at Microsoft at the time and covers the differences. Very interesting read.

[xorblurb]

I agree, that book is excellent.