I try to remember the concept when I’m a student. The student should be engaged, curious, and ready to learn. The “You can lead a horse to water…” (a less graceful version of your quote) concept summarizes the student’s responsibility in the learning process.

I think differently when I’m in teacher mode, however. A great teacher can sometimes win over a reluctant student. While there is nothing to be done for a totally disinterested, passive student, a particularly inspiring and passionate teacher can win over a student who is on the fence. So I try to set the bar high for myself when teaching with the hopes of having an occasional victory.