Unless they give you fair warning.

College professor on the first day of class says "There are 40 people in this class. About 3/4 of you will not make it to the final exam. I expect you to learn a LOT and if you're not prepared to study hard then you should drop now." Sure enough, there were only 8 students left to take the final. It was an anatomy/physiology course designed for people wanting to go into medicine or nursing and she didn't fuck around. Most of them were so used to easy courses that required zero studying to pass that they didn't take anything seriously. It was designed to weed people out, but they had fair warning. She was an excellent teacher, one of the best teachers I've ever had, but a lot of the students were simply not cut out for medicine. Better to get a reality check early when there's still time to reconsider your life goals.