There's a thousand little unique skills, and they're all important. Some of them include communicating with your team and managing team morale.

Additionally you get matched up with 4 people who roughly have the same sum of skills, which almost certainly means a completely different makeup of skills

So you notice your teammates screwing up all the things you're better at, and you naturally overlook your teammates skills that don't look like your own.

This basically manifests as road rage where the driver doesn't realize he is the traffic. It creates a situation where nearly all your teammates look like idiots compared to what you look for. Because you're not looking at ALL the things.