I think it's a reference to the book "How buildings learn". I haven't read the whole book but as far as I have read it goes like this: people try to guess what

I think it's a reference to the book "How buildings learn". I haven't read the whole book but as far as I have read it goes like this: people try to guess what the good building supposed to be and build it but later they have a change of heart or either some other people move to that building and have completely different outlooks of what their home should be like. Author argues there is levels to buildings and we should build bottom levels in a way that won't hinder later changes to upper layers because the bottom levels are unchangeable and you would be better off destroying and rebuilding it if you want to change those bottom layers. Software seems to be related in a sense that the bottom layers of your app should be developed in a way that won't be in the way of developing new features because if that happens you would need to rewrite from ground up.