This holds true for me as well. I'm good at keeping my commitment where I am invested in the people involved - students for me or colleagues I write with. While I enjoy projects more that don't have deadlines, where I can just spend a lot of time reading and thinking about the subject, I could do that indefinitely and never get to the point of writing down what I have learned. Learning or working through the question seems to be its own reward. Not helpful in academia. I'd like to harness discipline better for my individual projects bringing them to fruition.I have to use feeling to keep me motivated. Once I stop caring about something, or stop having an emotional investment, I can easily quit.