well you may already know this but just incase, high rank people need to lower there battle ranks so they can find matches easier, do 1v1 with there friends to help them lvl etc. so they join a 1v1 with no weapon or deck and there rank goes down. hope i helped
I leave (in 3v3, 4v4 matches) if the other team is chain stunning. I would rather stand in the corner for 5 minutes waiting to PVP again, than to read the comments both teams are making and standing stunned unable to even pick my nose. I won't give the chaining team the satisfaction of defeating me in person.
While there are many possible reasons why, some of which have been mentioned here, the most likely explanation is that they are ranking down.
As folks have said here, ranking down is what players do to lose rank, as in go down from Warlord to Private. The primary reason folks do this is so that they can accumulate tickets FAST. Imagine if you're a Warlord and you enter into a 1v1. You might battle for 15 minutes, an hour, MORE than an hour, at the end of which you might get a win and 10 tickets. But you could also get 3 tickets if you lose. In that same period of time you could get a guaranteed 15, 24 or more tickets by entering battles and losing right away.
While this isn't fun for either involved, nor does it take any skill, it's a quick way to amass Arena Tickets. More tickets, the sooner you can get your Commander Gear.
Its also of note to say that's only one reason folks rank down. Another is that there are some inherent disadvantages to having a high rank - namely, you wait FOREVER to get matched up. Warlords higher than 1600, or 1700 rank can expect up to wait up to 30 minutes or more for a single match. And the higher you go, the longer the wait. Not fun.
Either way, signs that someone is ranking down would your opponent doesn't have a pet and doesn't have a wand (only has one pip).