Cursing with all caps at an ally that failed to do a simple task is just about as useful as a square wheel. Be wary of how you communicate with the team. Learn to give credit when it’s due, be vocal about awesome plays, and be constructive when giving criticism. Not only will flaming allies ruin their mood, it also makes them less likely to cooperate or listen to you later on. Keeping a level head and staying positive can also do wonders as in most cases, one good fight can turn the tides.
Since the internet at large is filled with monsters, being nice in-game also has its effects in game. As DOTA 2 continues to improve the game, the community is expected to be courteous with fellow gamers as well.