You want to know one thing that separates a good from a bad player?
Knowing what they are playing against.
Lots of people are complete literal retards when it comes to this.
If, for example, I see the enemy team not having an ADC sure I will go in on them and most likely win a fight.
If, however, I see an enemy team not having an ADC with them but they have a Twitch on their team, I will not go in until I know twitch is hiding somewhere.
His ult isn't the problem, it's the people that play against him that are.
Think about that champ, and many others, as Retard-Weeders.
You've been weeded son!