End of the ranked season trolls

Why do players who almost never play ranked feel inspired only to rank when the season is about to end? There are so many games lately with players who don't have the same competitive dedication as many other players and will give up games easy, and just don't care about the games in general. So many players who just don't care ruining the game for people trying to complete their goals they've been working for all season long. Not to mention the many trolls who decide to ruin the game for everyone, I've seen Janna jg with a pantheon support in a game, twitch top lane etc, and all of them are just playing the game in a non competitive sense. In not saying non-meta champs are necessarily trolling the attitude these players have give it away. I've also seen many afk games lately. People just don't care. They really don't. Its sad to see a community of players who ruin it for the ranked players. P.S This is referring to another one of my accounts.