The person who finishes learns lessons starters never stay long enough to meet.

The last portion of a project teaches things that are simply unavailable earlier, about how a thing behaves when it is nearly whole, what breaks under real conditions, and what you get wrong at the end. Someone who starts constantly never encounters any of it and repeats the same early lessons.

Choose one thing and take it all the way through, even if a newer idea is more appealing. What you learn in the final stretch does not exist anywhere else.