Self-awareness is terribly important. Terrible at times, but also important for everyday life. I think everyone out there has that one friend who has no awareness of what their talents are
I am not talking about those over humble friends that don't realise that they are gifted or lovely or beautiful. I am talking about those friends who think they are many things but are, in fact, terribly ordinary. Those friends who constantly show off 'talents' in which their performance is actually very mediocre.
I have a number of friends who think they are really deep and gifted writers. But you cannot tell them their poetry is awful or that promoting their 'short stories' all over facebook is embarrassing. The very worst is those people who, while they may not be bad at something, the very fact that they think they are talented at something makes their mediocrity all the more painful. This most commonly manifests in singers (usually girls). Now I myself cannot sing, and I do people the courtesy of not pretending to have any skill in that area. I do however have a number of friends who call themselves 'singers' when they really do not have a good voice. They can carry a tune yes, but their confidence causes them to try to sing well beyond their range and limits. A truly good singer adapts songs to their abilities while the unaware sings like they are Adele when in fact they're more in the region of Ke$ha. It. Kills. Me.
Now I'm not saying that confidence and a bitta balls aren't admirable traits, but over-confident people are incredibly hard to get on with, especially when they don't have the talent to back it up. I don't want to read your bad poetry, especially when you expect me to tell you how moving it was; I don't wanna watch you sing when you expect me to clap; I don't wanna tell you how 'awesome' and 'unique' your outfit is when you look totally normal. I once heard a great traceur (parkour practitioner) say 'Never tell people you're good, if you're good they'll tell you'. I think there are plenty of people who could benefit from this kind of thinking.