Personally I think this is stupid as most people play timed games and if someone wants to use their time they can, but many disagree. Assuming you aren't doing the first two, it's possible that because you aren't used to the interface you are playing slower and impatient players want you to play faster. In my experience the main reason people get kicked after a game starts is being abusive in chat, intentionally sabotaging their team, or consistently slow-playing. Once you get to level 2 it should hardly ever happen.
Eventually you'll establish yourself on the site as not a completely new player. I see it often and although it's bad etiquette there isn't much you can do prevent it except keep trying to find games where people will play with new players. If it's before that's just people being overly selective and not wanting a game with a new player. Do you get kicked before or after the game starts?
