I try and finish a project before moving on to another one.

Otherwise I get in a trap of starting projects, having loads of fun making stuff and being creative then getting bored of doing the fiddly methodical work at the end.

Depends if you're disciplined about attending to all the stages in a project. I'm lazy and easily distracted so I make myself finish for the sake of getting stuff completed. Otherwise i'd just have a hard drive full of WIP that I can't be arsed to finish.....