The problem I have noticed with rewrites is that the people designated as the "architects" feel they need to design everything in such a way that it can handle

The problem I have noticed with rewrites is that the people designated as the "architects" feel they need to design everything in such a way that it can handle every possible new feature request. They completely don't understand YAGNI. So, I have seen several rewrites at several companies completely fail and take millions of dollars with them.