Overcomplicating

Running ten miles a day is easier if you already run 8 miles a day. Running a very fast time is easier if you've already run a fast time, which is easier if you've already run a kinda fast time, which is easier if your goal is just to run a bit faster than you ran last time. I am not advocating against ambition; I am advocating splitting that ambition into humble goals and giving yourself the chance to achieve them, and then using the motivation that comes from accomplishment to stack those humble goals until you've done whatever it is you set out to do.