I'm not sure about that.

Good-looking people have a head start in life. Other people want to be around them and to please them. There's a theory called the 'Halo Effect', which suggests that we automatically imagine that people who are superior in one respect are also superior in others. We see a person who is tall, with glossy hair, clear skin and good bone structure, and instinctively presume that that person is also intelligent and capable. We would judge them to be a better teacher than the ugly person with bad skin and an unflattering hair cut. We'd also work harder to please and win the approval of the better-looking specimen. It's human nature.

If you want to learn a language, we can suppose beauty isn't the main factor in deciding for a teacher... And, since you want a teacher, we can assume you do want to learn a language. You can find beautiful people everywhere, it doesn't have to be the teacher.

Maybe not. If you choose a teacher you like. You will try your best to communicate with her/him. Perhaps you will get improvement very fast. HaHa

I agree that you shouldn't choose a teacher for their beauty, but I also think that it would be a mistake to avoid a teacher because they are good-looking since there are many presentable teachers who are highly skilled.

I am learning Spanish and most of the profesoras I have run across have been pretty. If I avoided all of the teachers who were good-looking there wouldn't be many left!