25 points
You’re assuming good faith and willingness to learn/change in the part of the students. I was a TA at a private US uni for the not so smart kids of rich parents. Our approach (imposed by admin) was all carrots all the time. 20% seems fair, even low, for the share of students who were there to get a degree with the least amount of effort necessary and then get a job thanks to the uni’s name and their connections.