I would go with rejection over not knowing. In fact, tomorrow I plan to ask this guy who i've been flirting with for awhile, and sort of gone on a date with (we went on a 3.5 hr hike) why he hasn't asked me out? I totally could get rejected but not knowing sucks. Now if I thought I had no chance with him I would never ask, but he's shown complete interest besides the not asking. Which probably has to do with the fact that he's eight years older and sort of my boss, not to mention an intp :/