atces.com
Agreed. Some of us instruct because we've been asked to do the job.
I'm an ATC instructor and OJTI because I was asked to do the job. I think I do a reasonable job at it as my success rate with trainees getting ATC endorsements is 100%. ( No, I'm not also checking them!)
I also like to think I do a pretty good job just being a controller. My check reports indicate this as well. Although Tobzalp will tell you that he'd rather work with a lucky controller than a good controller.