I would also like to add that you should get to mvp as fast as possible so that you can charge for whatever you've built.

I think a lot of devs focus too much on coding and not enough on revenue. Make sure the feature you're adding has value, or else you're just wasting your time.

I also made the mistake of using the project as an opportunity to learn new technologies which is dangerous because it can eat into the time it takes to ship.