All in all, finish what you start. It makes you a better and more accountable writer. I believe once you get over the hurdle of your first project it is smooth sailing from there on, or at least that was my experience.
Finishing what you start is also a good to think about when talking business. I mean if you’re a self published author you can’t exactly write the first book in the series, then start the next but never finish it. As a self pubbed author you have to be prolific in order to make it these days. One hit wonders do happen, but keep in mind that they are a rarity. It’s pretty much the same with traditionally published authors, only with them they’re breaking legal contracts.
I wish yall some luck in your writing adventures, remember be accountable and finish what you start!