People tend to draw ideas from what they know. Therefore, if you have more experience then you may have a deeper well from which to pull ideas. You may have multiple wells of varying depths depending on the emotional value that each one carries.
I can identify key points in my life that are associated with certain successes, failures, or even herculanean efforts, that have been burned into my mind. That's where I go when I need a creative push.
I like to think of experience as having layers that can be pulled back to expose something similar, but different underneath. Emotional, mental, physical, or spiritual may be one way to break down a situation. Or maybe the layers are economic, social, political, or cultural. Depending on your perspective, a moment in time can be viewed from an endless number of points.
Deepening your well comes from getting out to see more and simply opening your mind to new perspectives and experiences. World travel no doubt helps, but so does reading and simply becoming more aware of what's going on around you.
The mind is like a cavern or a palace filled with knowledge, thoughts, and experiences. Only with through exploration and introspection will you find the treasures you need hidden in the corners.
I thought the picture used with this piece was interesting--it appears to be a tunnel, but with the reflection in the water, it also appears as a well.