Quit after 17 hours dual after my instructor wrote "This man is dangerous!" on my last lesson notes. He said I'd never be safe to fly solo.
Fourteen months later I tried again at a different flight school, did 3 hours dual then my first solo at 20 hours TT.
Years later I have FAA CPL/IR, multi-engine, aerobatic and taildragger experience, Tanzanian CPL, CAA ATPL exams pass and commercial African bush-flying experience.
Just goes to show a bad instructor can break you, and a good one can make you.