They end up solving a problem that someone already solved. Worse ! In development they end up creating a poor replica of what someone already did.
We call it the inner-platform effect.
You can see analysis paralysis is getting you, in every field, when you start asking so much "what if..." that you can't even start.
In life, best practice is to find an easy and clear next step which can be done in less than 1h that can help you move to your goal.
In development, we write in code what should work correctly in the next 20 minutes, we call it unit testing.
Different domains, different words, same philosophy.