The systems we like to rewrite from scratch also tend to be complex with many layers of abstraction and integrations. When we change something on them, it doesn’t always go smoothly, particularly if we’ve slipped up in our test coverage. The more problems we have making changes, the more we overestimate future failures. The more a system seems brittle, failure-prone, and just impossible to save, the more a full rewrite feels like an easier solution.
This is probably every Drupal project I have picked up.
