If you don't get it the first time

...perhaps you should change your approach.

Students get this wrong all the time, by assuming that if they only make more of an effort (at listening to, or reading, or watching the same thing again) they'll "get it" eventually.

And teachers make the mistake of assuming that if their students aren't getting it (the first time or even the tenth), it's because they're not listening or don't care. When, in fact, they really just might need a better explanation.