I’m no great teacher, but I was able to get all but one of the office hour regulars up to speed over the course of the semester. The first part of the sentence is in direct contradiction to the second part. If you did that, it means you had patience, were willing to explain, re-explain, and find alternative ways to explain. And you cared .
So much truth here. Especially the fact that you cared. As someone who had his share of poor TAs and was a TA, caring is what sets apart the good teachers from the poor ones. Taking the time to sit and figure out the fundamental misunderstanding and then a good way around it is essential. It may look obvious to you, but the other person is obviously lost. The only way to solve that isn't by special power or teaching…
You need a deep understanding of the material, obviously. You need to have a model of the correct thing in your head. The empathy bit comes in from first caring, but also being able to quiz the student's understanding so you can start to understand what the (incorrect) model is in their head.
Then you need to figure out how to build a bridge between their model, and the correct one. And you may need to build multiple bridges if the first one doesn't take.