A fellow employee, Margaret, contacts you and asks, "Do you know anything about [problem] and how I might be able to solve it?" You respond, "Oh, yeah, Jane is handling that now." You are a busy person being crushed under the weight of your duties, and you have just helped someone. Having now pushed something off of your plate, it is time to address the next thing!
But then Margaret comes back to you and says that Jane isn't sure why you said she could solve this problem. Jane is confused, you are confused and Margaret is left floating in ambiguity without any direction nor answer and must go ask someone else and begin this cycle again. If this conversation happens via email, expect it to take multiple days and span multiple threads.
Why did this happen?
When someone reaches out to you and asks a question, and you believe someone else has the answer, then you are now effectively a hinge between these 2 people.
You are what connects that person's problem with his/her solution. When you do not act as a hinge does and connect the two different parties, then both remain separate (read: you will now spend significantly more time than you would have originally spent figuring out a solution).
Delegating responsibility and empowering others are pivotal skills for leadership of any sort. How does it feel when you ask someone for their assistance, and they are incredibly helpful in getting you where you need to go? It feels pretty darn good. Why? Because you have a guide that either knows the way or knows someone who does. You know that you are in safe hands and that your problem will be solved. You have a clear path to a solution and are thus empowered.
If someone asks you a question or comes to you with a problem, it is because they believe you possess the solution. Instead of dumping them on to someone else, it might be in everyone's best interest to set up an introductory email/Google Hangout/Skype call to act as the hinge you are and hand one person off to another for safe-keeping. This way, you leave nothing to question, and if there are any issues, your group will immediately be on the same page and be able to find a solution much more quickly.