I think that for me, getting irked has helped me to distinguish between knowing when to just let go of a project I'm working on and when to allow myself to continue experimenting with composition, light, and angles and such in order to get what I consider to be a satisfactory shot. If you're going to get so mad at a project that it turns photography into a chore instead of a fun thing to do, then its time to take a major breather and move on to an easier photography project, perhaps. I hope I'm making sense.