I was playing Arma 3 on a tactical team. I was the min helicopter pilot for my unit and I had to drop squads off on a building rooftop. Let's just say, I landed they got out and when I took off I wasn't paying attention and crashed into the next door building. Oh also I was playing csgo and really messed up a flashbang, it hit our entire team and then a guy sprayed us all down with a p90.
When Dota 2 was created. Or rather, when any MOBA was created. Yeah those were the worst fails in gaming.