A fair point, Frank. And that's why I stated I've seen some instructors that were good despite being motivated by ego. However, it's apparent from some of the responses here that many find instruction from a place of ego negative. You yourself reacted to olafhardtB's post with distaste.
After my "softening" of his post into a more clear point and observation, we see a defense of ego as a motivator.
And, yes, to some degree, ego probably is a motivator for much at which we wish to excel. And yes, we're now branching into psychology, and I am no psychologist.
olafhardtB took it to extreme.
...all those innocent eyes looking like I am God almighty...
Though, he did preface his confession as "awful." And as he phrased it above, I agree with him. It's awful.
Ego can be a really, really bad thing in instruction. I've seen that first hand. And I personally find a difference in ego-motivation versus some of the other motivations that have been listed in this thread.
And since I'm referencing that, now seems as good a time as any to list my own motivations, since I'm the one that started this thread.
For me, it's about power.
Now, if you read that, you might think, "christ, he's after power." Except, for me, it's not about "power" as an instructor. It's certainly not about control of or influence over my students. Power is the root word of "empowerment." I had an instructor say (in the most unlikely of settings) just last week, "warriors
choose to be pacifist." This was an instructor at most of the most liberal universities you can imagine. For me, instruction is about the transfer of power. Good defensive instruction infuses students to some degree or other with the power to defend themselves and theirs. It is a power of self-reliance. And self-reliance is the foundation upon which this country was built. Self-reliance, self-defense, and even on the macro scale, self-governance. I enjoy passing on a realization, that one does not have to rely on others for the defense of that which is truly most precious. Life.
Ego can get in the way of that transfer.