Coaches and players have a window in which they can get away with losing. But at some point, fans and programs demand results. There is also a limit between conditioning and talent.

Back in the 80's, summer practice began with two-a-days. All indications were those were tough workouts. The training staff and coaching staff are key to make sure no one gets hurt.
I forget when Beamer stopped having two-a-days to open August practice. Now, the goal is more of a year-round athletic regimen.