As an insect photography enthusiast, this sort of thing really drives me nuts:
You look at the photo and realize that you ALMOST got a great shot, but there’s something glaringly wrong with it. In this case, I’d focused on the wasp when it was sitting on the flower and it decided to fly away between the time I focused and clicked the shutter release. As a result, the wasp is out of focus! So annoying! If I’d just been a few millimeters closer to the wasp, it would have been awesome. Alas, it’s out of focus and it’s the only shot I got. Sigh… What can you do? Sometimes that’s just the way things turn out, but it doesn’t make it any less frustrating.