Leaverbuster is CRAZY Inconsistent

Honestly, I think that the title says enough as it is, but allow me to provide some context as to why... Once upon a time (August of last year), I was enjoying my time playing some league with a friend, and my league bugsplats. I attempted to reconnect and my league bugsplatted a second time. Already a bit frustrated and expecting a leaver by the end of the game, I finally managed to reconnect a third time. Then, my mom calls me from downstairs. Ten minutes later, I come back to computer and see that I've disconnected from league AGAIN. For the FOURTH TIME I try and reconnect and see that the game already ended. And guess what? I DON'T GET A LEAVER. And now, all these months later, I disconnect from being afk because my mom wanted me to go do something else, I reconnect, continue to play the game for another ten minutes, we lose, and I get a leaver. RIOT WHY?!