I've seen equally many projects never achieve lift-off because they were stuck in analysis paralysis trying to architect MVP for scalability, extensibility etc.

I've seen equally many projects never achieve lift-off because they were stuck in analysis paralysis trying to architect MVP for scalability, extensibility etc. And even if that succeeded you often end up with fear of change because the complicated architecture can't be touched. It's really important to have the right balance here, but KISS and YAGNI are often easier to scale when you need it, than the reverse. If you don't have the mentality that the MVP must never be rewritten.