Tonight in a forum someone told me to shut my big mouth and called me a jack of all trades and master of none.

Now, I can understand the first bit (it's not like nobody's ever told me that before). I don't entirely get the second though. I THINK they were making the snide implication that because I multi-task and have more than one interest, I'm not good at anything that I do.

Why would someone make that assumption? Why is it so hard to believe or recognize that someone just might be able to do a number of things quite well?

Granted, there are a lot of things I do NOT do well. Mathematics, for example. And physics. And chemistry. And pretty much any "hard" science. I can't program, either, though I can sort of hack up code a little bit sometimes, if it's pretty basic. I can't fix cars, I can't fly a plane, I can't play any instrument with any degree of accomplishment. Can't dance (well, I can bop around like a fool and enjoy myself, but I wouldn't call it dancing), can't ice skate, I mean, the list goes on and on and on of the things I can't do or (and this is an even bigger list) things I know very little or even nothing about. The universe is absolutely full of things about which I know nothing, and about which I would never pretend to know anything, because I know better than to bluff like that (I hang around with geeks; geeks call you out on stuff like that).

I'm just wondering what sort of narrow thinker believes that if you do more than one thing, you can't possibly be good at anything you do?