Earlier quoted context omitted.
The practice to awakening odds are pretty poor. If you were to ask your fellow practitioners how many of them felt as if they fully grasped (experienced) the teacher's teaching, I'd be shocked if more than 1 out of 20 said yes. Add to that the fact that practice in the Buddhist world is almost always an ass kicker of the highest order (hello screwdriver in the knees), then one wonders why take it up in the first plac…
Saying that, I did meet someone who awakened without a teacher. I suggested that he attend a couple of sitting groups that I used to go to. After the Dharma talk/discussion at each group, without having said a word, both teachers came up to him and basically said, how on earth did you do that? That's an awesome story. I'm only scratching at the surface, and something tells me that it's going to take a lot longer than…
Hang on a second, there is no you, how could you not be awakened?
Then why practice? Good question, it must be that delusions are endless; otherwise, we'd be lazy in the most wonderful sense of the word (see Ramana Maharshi for example).