Short and sweet.
The serious photographer holds a great picture in their mind as if it were a poem. While they know the picture well, they improve on the picture the whole time, re-working it, adding accents, changing the flow of the imagery and doing it over and over until each stanza in the image is perfect. The great photographers revel in this process because they know that once complete, the picture/poem is perfect. And that perfection will last for generations. It will be something that can be shared, kept and protected forever.