>>64166734The outcome in Dota is usually down to planning rather than pure damage numbers, someone can separate you or ambush you no matter how far ahead you are. People die just as fast, but there are tons of stuns and save abilities so positioning/foreknowledge makes or breaks a fight. Entering the enemy base to end the game is particularly dangerous (since it's uphill and you can't see them) and your enemy can get a second wind if you fuck up. Bad players can often be protected and are useful as distractions and their deaths reveal useful intel, plus a lot of heroes can still contribute with a stun or something. Precious milliseconds wasted on your friend can easily get the enemy carry killed.
The problem in League, as I understand it, is that feeding kills digs you into a hole you can't get out of and you always need to play safe and fight at full strength. If you're behind, you can do very little except stand back and try not to die, so by extension if you have bad players, you spend a lot of time doing nothing as they die repeatedly.