I won't find the post, but the advice I read here that worked for me was something like : "If you want to do a project and are scared of the size, just start and see how far you can go".

This really lifted the pressure off. It doesn't matter if it doesn't work in the end, just see how far you can go. It's really simple.

This allowed me to launch a product, make a few thousand bucks from it, and then fold it, cause it wasn't such a good idea.

This same advice allowed me to finish the 1st version of a screenplay I wanted to write. I am in the 2nd version now. We'll see where it goes.