Two misaligned incentives that combine to give us the state of modern tech:
1) Volume of deliverables is more visible than their quality
2) Putting out fires is more visible than preventing them
Also, having worked at a 'half-baked MVP' factory, I find that in that environment teams prefer to let things bloat until they have to do a "redesign" that they can show off to leadership as a big (and noble) undertaking.