It's different from just being a pilot, or from being a student. You would think that would be obvious and not need comment, but just as the actual fact of being married is different from your expectations, being the CFI responsible for not only the safety of flight, but also efficient transfer of knowledge, is very different from what you might think.
I've done some instructing before. Prior to even having an instructor's license I taught my oldest daughter (Thing 1) the basics of aircraft control, and even had her able to fly a full traffic pattern and approach, everything except the final moments of touchdown on the runway. Then she lost interest and hasn't flown since. I have an instrument student "D", but he can already fly safely. My responsibility is only instructional - to teach him how to fly and navigate only using instruments.
My new basic student, "D2" already has 30 hours or so, and has had 2 prior instructors. He's not happy with how quickly they were progressing, I suspect because he is a perfectionist, and since I know the other 2 instructors, who are the same way, I can see how they would keep on polishing and polishing the same skill over and over, and not move on once it became "good enough". In this sense, good enough means he can perform the skill to PPL standards most of the time. I believe once we add further skills, the current stuff will become second nature and just need practice before the test.
So yesterday we started on traffic patterns and landings. If we'd had an office space or a desk, we could have (and should have) gone over the traffic pattern procedures with him in advance, but since I hadn't flown with him before I didn't know if he was good enough yet. Well, he is, so we did 3 circuits at Mesquite. By the 3rd one he was picking it up, but it was starting to get dark and the cloud base was dropping. So tomorrow it's back to pattern work, but this time with a thorough pre-flight briefing since I can have a firm plan..
We're both learning here.