it depends on your personality. i like change. i do not like anything to remain the same - for the most part anyway. so i prefer to have a few projects going at once. depending on my mood is what i work on. many times i will be working on a project and get another idea for a new project. sometimes i start it and sometimes i say, okay as soon as you finish this one you can start another one! this year i have been finishing many ufos and i'm feeling really good about it. the best way to do things is what feels best for you!