I've found the nature of the idea is quite important as well. For example for a long time I used to do very "philosophical" projects. Huge ambitious ones wher

I've found the nature of the idea is quite important as well. For example for a long time I used to do very "philosophical" projects. Huge ambitious ones where before you even start you already know it's by definition going to take years for it to get to somewhere worthwhile. Except I wasn't ready to commit to such things, and I knew it. That tiny half-assed part of a huge project will not amount to anything. So overtime I accumulated a great graveyard of "this would be cool if I had worked on it for a year instead of 2 weeks" projects. On the other hand if the idea is small and practical you can work on something for 3 weeks and have something nice and practical that is a concrete achievement. So if finishing is your goal and you don't have tons of time to dedicate to a project my advice is to ask yourself how practical and realistic is it for you to finish an implementation of that idea in your desired time-frame? If it's a huge idea you have to accept the reality that in your amount of time you can't finish a significant % of it. And 5% of a huge project is often not as useful or impressive as 120% of a tiny project.