As if it weren't already obvious, I like to think about guitar as well as teaching it. It's a little bit to do with the stuff like money or getting clients, and much to do with the actual relationship between teacher and student. The latter, for some reason, fascinates me.
I believe that any subject can be ultimately broken down into small manageable chunks, which I like to think of as "quick fixes." One thing however that quick fixes cannot change is helping a student play guitar who doesn't want to do it. To paraphrase a potent analogy, it's like putting ice cream on top of poop. There's no quick fix for someone who doesn't want to play.
I think that there are just thousands of fantastic ways to show people just about anything on guitar, if they want to do it. Teachers can unintentionally hurt a student's desire to play by asking for too much. Sometimes, teachers can sap the student's enthusiasm by asking for quantum leaps in development, overnight. Disgusing this by saying, "Well, you need to practice okay?" is just not cool. It creates a huge amount of stress for a student, one who might just be in it to have fun. It makes them not want to play guitar AND it makes them feel bad about it. If you are a guitar teacher, do you really want to do that to someone? If you were studying guitar again, would you want a teacher to do that to you? Is it fair?