In my case, I might teach a very gifted student for free, or a very sincere one, but I would also expect more of them since they are getting it for nothing. He has a medical practice and to take time away from healing his patients for a poor student is something he deems wasteful. Another post advocated learning basics from video as opposed to learning from a teacher. This logic was based upon a bad experience with ONE teacher. ONE teacher is hardly a good sample size for such a conclusion.
Teachers are necessary and good ones are hard to find.
THAT is desire and dedication worthy of consideration.