Why dont MMA fighter`s turn to boxing?

[Leighton]

Actually it was MMA fighters going into BOXING

I know. And I would give them the same chance of suddenly going over to boxing and winning a fight as I would give a boxer of going over to UFC and winning a fight. Not alot.
Thats how the discussion startded but other people said that a boxer could go to UFC an win but not the other way round. That is why we are at this point.