Among many teachers I meet, I have noticed a trend that it has taken me a long time to realise applies equally to me. This trend is summed up by the phrase:
"Those who can, do. Those who can't, teach."
(* There is also an addition to the phrase, most oft heard at teacher trainer schools:
"… and those who can't teach, teach teachers!!!”)
I have always disliked this ugly phrase since first hearing it as a child - after all how could you have teachers who were skilled at what they taught or skilled people who can pass on their skills? - but I’d also noticed that it was often somehow accurate. Capable people chose to teach what they chose not to do. Teaching is all well and good - for how would anyone learn without teachers? - but should it be at the expense of doing?