Why do some people choose the dumbest or unlikliest answers for best answer?

i really can't figure it out. i have seen some really great answers passed up for some really out there, really stupid, or even really clueless answers. and no, i am not just talking about my answers...i have been browsing friends answers and found the same thing. does the questioner not really care who they chose for best answer...not really want a good answer?