When asked about how he built his steel empire and managed to turn over three dozen people he had hired to work for him into millionaires (quite an accomplishment for the 1930's), Andrew Carnegie replied:

"Men are developed the same way gold is mined. Several tons of dirt must be moved to get an ounce of gold. But you don't go into the mine looking for the dirt."

Wise words coming from one of the most successful businessmen of the 20th century; real leaders help those under them find the brilliance within themselves, rather than trying to instill it by fiat.

But I would go one step further and ask: why kind of gold are you looking for? We tend to go digging for a particular type of mineral depending on the person we're dealing with. We don't usually ask the receptionist her opinion about the marketing strategy. Programmers don't ask the sales people their opinion about a problem they're having, or vice versa.

Part of this is out of consideration for the other person...when dealing with problems in different domains, you don't want to burden someone with reviewing your work. But assuming the other person is able and willing to quickly offer their opinion, we don't always ask for it, simply because a critique of our work is an uncomfortable thing to face...especially if that person isn't in our department or if we don't think they're as skilled as we are.

We have goggles we use when panning for gold; I'm not convinced we always know it when we see it.