Why are flies so darn annoying?

Question

What causes house flies to be so annoying? I swat at them and miss them and then they fly back onto me.
It seems like they'd want to leave me alone if I'm swatting at them but no they just continue to bug me.

Answer 1

Flies are attracted to the Carbon Dioxide that we exhale and they love our exposed skin.

I have to sleep with the covers over my face to prevent flies landing on me and disturbing me while I sleep.