EWH
As an employer I used to think " That guy is great, but what am I going to do if he quits?".
It has happened, my top guy got a better offer from a competitor that I was unwilling to match.
So then I am more careful in how I train people, because if I show them too much they will leave.
You can see how self defeating this is, you end up with a bunch of guys/gals you have to nursemaid who do not expand and grow.
At which time they are all dispensible.
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor