There’s one simple question you should be asking your employees when they come to you with a challenge or opportunity: What do YOU think?  And as often as possible (when true) – follow up with, “That’s a great idea, now go run with it.”
This question accomplishes several things:

1) The employee appreciates that you want to know what they think
2) They take ownership over the challenge/opportunity
3) They garner buy-in into the solution because they helped to form it
4) They may have an idea you wouldn’t have thought of that’s the best solution
5) You slowly teach your people that they don’t need to come to you for every decision – that often they can trust their hunches*
6) Which allows you to no longer be the bottleneck, thus increasing the speed of progress
*Yes, they will sometimes not do what you would have done, and most of the time that will be okay, and when it’s not, they’ll learn from their mistakes and be more knowledgeable employees.