Teams can get a mentality, based on what happens. Doesn't have to be an intentional tank if you lose a lot, just human nature for a lot, maybe most, people that if you try and try and try, but it's not good enough, at some point your attitude can be poor, just get tired of losing and think there's no point in continuing to try.
Losing can breed losing, just as winning can breed losing. Didn't we hear Cowboys players saying years ago that they felt as long as Roger was in the game, there was a chance to win, even in the last few seconds? Why? Because he and the team had done it. They would try their best all the way to the end of the game because it was possible they could win.
How many here said the team "quit on Wade Phillips"? After some tough losses, that sentiment was rampant among Cowboys fans. Was it true? Maybe, maybe not.
I just don't like trying to lose games, too easy to get accustomed to the fat paycheck and lose the desire to really try hard...