Many mathematics professors don't require homework to be turned in for grading. For example, the calculus courses at many US universities. Grades are solely determined by quizzes in the discussion section and by exams. Failure rates are above 30%, but that's accepted.
This model won't work for subjects that rely on students writing reports. But yes, universities frequently accept that failure rates for some courses will be high, especially for engineering and the sciences.
This model won't work for subjects that rely on students writing reports. But yes, universities frequently accept that failure rates for some courses will be high, especially for engineering and the sciences.