Why does Siddhartha distrust teachers so much?

Siddhartha believed that you could not gain wisdom from a teacher..... you needed to learn from experience.

Knowledge can be conveyed, but not wisdom. It can be found, it can be lived, it is possible to be carried by it, miracles can be performed with it, but it cannot be expressed in words and taught. This was what I, even as a young man, sometimes suspected, what has driven me away from the teachers.