Finding a photo

From a 2point8 article about sending Magnum photographers to South Korea:

At least one theme—religion—featured a few larger prints, as well, including a picture I wondered if they’d find, of churchgoers with their eyes closed and hands in the air at one of the more fervent Christian churches in Seoul.

So, how much of making a photo is just a matter of dropping a photographer into a certain situation? Is there really that much "work" to be done once you're there?

(I'm thinking here only of "street" photographers, by the way.)

There can be improvisation, but it is only a bodily one—the work of getting oneself to the right position (concretely: perspective) to take the picture, such that it aligns itself with your broader collection of photos (vision, in the most basic sense possible).