It is a general belief that when you make a mistake in playing you should repeat this place hundreds of times until you play it correctly. But if you continuously repeat your mistakes you only become better at doing the same mistake, since you are just practicing doing it again and again.

When you make the same mistake in your lesson, and the only comment of your teacher is that you should play this section another few hundred times, you are right to question your teacher's competence.

My advice is that if you repeat the same mistake three times you have to stop, think it over and change something so as not to reproduce it any more. You may need a change in your position, in the technique you are using, or to just play it slower. Whatever the cause, don’t stop making changes until you hear that it is nice and correct. Otherwise it will be always wrong until you  start hating this piece of music.

If you want a different result you have to change the way you are doing it. If you do it the same way you will always get the same result!