Inspiration doesn't just waltz through the door and hand you a shiny new idea. It also makes you smarter, quicker, better motivated, and more talented. (And, very likely, sexier!)
By giving you a clear and specific goal to focus on, inspiration clears away the thicket of indecision that often bogs down down creative work. It also puts you into a different state of consciousness, a thinking style with a slower pace and broader base. This enables you to take in more information, keep track of more details, and tackle complex, multi-dimensional problems with ease.
How does inspiration do this? Mainly by shoving aside all other worries and concerns that might occupy your thoughts. Inspiration also helps clear your schedule, by reducing the urgency of other activities (like eating and sleeping, for example).
With a singular focus, enhanced self-confidence, extra brainpower, and long hours of uninterrupted work, it's no wonder that you get top-quality results under the influence of inspiration.