Bribery kind of works in the sense that if you work hard you get rewarded.

From an education perspective, bribery is bad as those who are bribed work for the sake of grades and not so much for learning. Those who focus on high grades only may either focus too much on school and/or may not take risks. (Grades only matter in the short term and not so much in the long term due to forgetfulness)

If you combine bribery with cheating for high grades, then that can get nasty.

Another extreme is where some parents do punishments for failing. Some go as far as wanting their child to be a doctor/lawyer/engineer/accountant or they are a "failure". This is crazy as this goes against the child's wishes and it is not easy to be a doctor/lawyer/accounting/engineer. (There are other alternative jobs that pay well.) The child in this case would work hard to avoid failure.