M+ Leavers Suggestion

Im really tired of leavers in m+ . I have key and creating +10 group. I take only 2300+ rating and 620+ ilevel. Sometimes tank get spoiled and pulling too much adds and we are wiping. But until this time, we kill 2 bosses without problem. Then someone is leaving party or turn off the game. That ruins our keys, time and game fun. My advice is, everyone who joins someone's party has key too. If their keys also get -1, they cant leave at the first mistake immediately. They are relax. Its not their key. They dont face with any punishment but the key owner. Something shpuld be happened about it. Hear me GameMasters. A lot of people complaining about that. Well thank you