What aggravates me is when someone comes along and has this awesome idea and thinks it can be done with no problems.
When people feel that way about something, I invite and encourage them to do it themselves. Usually they will not try. If they do try, they will probably fail, but they will learn something. If they try and succeed, we all benefit.
If you are refering to me being aggravated about that, I am a system admin for microsoft, and linux servers so I get that type of "let's do this" a lot, usually from the ones who know nothing about how the system works.
I.T. - No one knows you exist until something breaks, even if it isn't your fault.