Do you ever find that you wander for a while looking for a subject and, when you find one, you take a while to find a compelling composition and then, while you're taking the shot, you start spotting more and more potential shots around you? I find this happens especially when I am using a tripod. It is through repeated experiences like this that I have realised what a contemplative act photography is.
I sometimes encourage this kind of experience by going to some location with my camera with no specific image in mind. When I get there I stop, stand or sit still, empty my mind and simply take in the scene in front of me, exploring the shapes, the colours, the lines, the textures, the light, relationships betwene different parts of the scene, the sounds and so on. Often, when I first arrive, I see very little potential but, after 10 or 15 minutes of contemplation I can usually not contain myself anymore and explode in a frenzy of shooting, trying to capture all the potential I've seen..
This shot, the previous shot and the next shot were created in exacty this manner. All were taken with the tripod in exactly the same position the ground, but at slightly different times as the twighlight progressed.