Ditto to that, and add that this can happen at a larger scale even if you happen to find yourself working for one of those lucky unicorns, where late-stage VC will swoop in, inflate the valuation, and dilute the hell out of everybody holding ordinary shares.

What I would love to know is how many people built these homebrewed systems at Google in 2007, then jumped to Facebook and built them again in 2010, and on to Uber to do it yet again in 2013.

I will make a heretical suggestion on the other side and say that unless you're pretty certain up front that your app will succeed, you need to get it in front of users ASAP, and if to you that means cutting corners on the SDLC and infra, so be it. If the app falls flat in the market, you'll never get a chance to amortize all that work.

Anyone at Google who's being honest and not just toeing the HR line will tell you that the easiest way to get promoted is to quit, go to another FAANG for a year or two, and come back at the higher level.