Did you submit a proposal for a conference before you actually learned/understood the topic you’ve proposed to talk about?
I’ve submitted proposals for talks on subjects which I have familiarity with, but need to research more thoroughly before giving the actual presentation. Preparing to teach others is an excellent way of learning a topic yourself.
I know someone who writes technical books on subjects he himself is just learning, because he knows that doing so ensures his books make sense to people who are themselves new to the subject. His books are excellent.