I can also observe this very often in other aspects of life: I find a new technology, buy stuff for it and when the stuff arrives at home to start playing around with it, I do not even open the package because in the end I'm thinking "not worth it to waste time on"... which actually ends up in really wasting time by just sitting on the couch and doing nothing. This exact same feeling I have when I have an idea for a new project but then I don't even start it.
It goes that far that even start to watch a new good movie, which was one of my biggest hobbies once, seems to be a too big barrier for me.
My life goals once were to have a family, a nice house and a healthy life. They are still there too, but somehow the "I need to do new things all the time" added up to the list, and this is contrary to the family and house goal. Maybe this confuses me, driving myself into two different directions at the same time?
The "start somewhere" is probably actually the question. Where?