Because modern software engineering ( cough ) doesn't do well designed or well thought out software any more. It is all about "Move fast and break things", while the phase was coined by Mark Zuckerberg, ( or attributed to him ), that mentality or philosophy largely came from Google during the Web 2.0 era.

This make some sense for Web Product development where you want to find a market fit, VC and media were all over it. But it doesn't work as well for Desktop and other type of Apps. Or in System Programming.

And it is funny we start seeing push back against it 10 - 15 years later.