Speachless

I came on after a while away playing Overwatch and Starcraft II and I decided to try League up again. I downloaded the game, picked my lane and waited. I was flipping through screens and looking over my shoulder talking to my wife when I noticed I had a 20 minute wait for a game. All of a sudden, I had somehow joined a game (?????), and left without even knowing it. There was no prompt from the game, no sound, nothing. It never let me pick a character. Just banned. What is going on? This game feels like it is designed to keep people from playing it. If the game crashes, you're banned. If it glitches, and you can't pick, you're screwed. Shouldn't this game be designed to punish leavers and ragers?