DCing in match start timer

What's with DCing just before the match starts? I've noticed this for a long time. I never disconnect from the internet or server during a game. It only happens before the game which is statistically unlikely to be random.

I just came up with a theory that it is disconnect due to inactivity. Sometimes I'm not using skills or moving while waiting for a new game. But I don't get any warnings about that.

If it is someone doing it idk how they have my isp. I play to have fun not socialize. I don't use teamspeak or join guilds.

What do you reckon?