I think that a lot of personal training regiments are set in the way that the person would fail. I see a lot of fat people like myself hire personal trainer that cost up to $80.00 per hour of routines where the PT treat the client like a dog and the persons huffs and pants doing the things that are intended for the trim people. I think that all this "doggery" is set that the person would fail sometime and would abandon the whole training thing and then would come back and PT would say something like "you see, it was your fault, not mine, that you were not be able to do those routines. Now, you gotta hire me back, train harder and do what I tell you".