Trollers

I guess this is just a shoutout to all the people who like to troll (What's up you assholes who ruin our games :D) and a rant about these trollers who like to ruin people's games (What's up you assholes :D). Okay so I recently played a game with a troll support, Anivia, She would just stand there and let the enemy team kill me as she stood next to the turret and danced. I tried to recall and I was about to recall as soon as the enemy team destroyed the turret, this Anivia walled me and let the enemy team kill me. I was trying to ult for a kill (I was Jhin) and she walls me so I couldn't use the move. So I just have questions for why people do this, and how can we fix it. (This was a ranked game btw and we lost ----_----)

1. Why do you troll games and ruin them for people who are actually trying to win the game?
2. How do you get joy from ruining something else for someone?
3. What can we do to stop trollers?