You know what sucks?
Playing with an adc that doesn't respond to chat messages, doesn't respond to pings, doesn't give pings. Literally 0 communication the whole game. Add this absolute trash teamwork in with the fact that they only split-pushed, always died from either jumping into the enemy team or getting caught split pushing. She never participated in grabbing any objectives with the team.
They displayed absolute trash behavior and clear trolling, acting like they have 0 game knowledge and don't know how to even know how to walk towards baron. Acting like splitting top as Elder Dragon spawns is a good idea...everyone in the entire game agreed they were trolling. They were only gold 5, but even gold 5's don't mindlessly do what this Tristana did.
The worst thing is knowing that they can hide behind the "but I was trying to win" excuse and they didn't do anything the system would detect to be trolling. They technically always worked towards winning by splitting or conveniently getting "caught out", and it's not technically a requirement to communicate with your team. It absolutely sucks knowing this player is allowed to keep doing what they're doing, and my report will have 0 effect on their account.
This may be a rage post, but it does shed light on how the report system is imperfect and the frustrations it can cause to players.