pencil tapping, the keyboard doesn't have the clickety klack, having one puzzle piece missing, you build a at-at instead of the milleniam falcon lego set, making an epic project and you don't get to present it.
those are the many things that people call "the most annoying thing ever"
"bro my game crashed after 2 hours of not saved progress, that is the most annoying thing ever"
School is the most annoying and irritating thing ever.