Usually, we are discouraged from doing anything that does not relate to the immediate bottom line of the company. While doctors, lawyers, and teachers probably work as hard as we do, their professional culture also encourages and supports them to regularly take time out and go in for a tune-up of their skills. I think that's why you see so many older lawyers, teachers, and doctors who are still practicing, but not so many older engineers. You should also consider our career path - or lack of one. When you're a lawyer, you can aspire to become a partner, when you're a professor, you can work towards tenure and maybe a chance to do some advanced work in your field.
Doctors get to pursue lucrative sub-specialties or start partnerships.
Well, um, we get to think about moving into marketing or management if we want to advance ourselves. From where I sit, it looks like we get to have all the responsibilities of professionals without most of the perks or respect that usually goes with them. There seem to be a few options we have open to us at first glance. Of course, the first one is to simply live with the situation and make the best of things - which aren't so bad at the moment. I worry though when this long boom is over.