what happens after you press the shutter

This morning, I read photographer Joe McNally's thoughts on the 40th anniversary of the "Napalm Girl" photograph, taken by Nick Ut.
"That photo made on that horrible day was made in less than a second. Yet a lifetime spun on its power. With so many photographs being taken everywhere, easily, and thoughtlessly, it’s easy to forget how powerful they can be, and occasionally are. I have always felt that for everyone, looking at a photo that means something to them induces an interior, seismic shift. It may be imperceptible, and not understood immediately, but your compass has been altered, ever so slightly, and you will never be the same again."
 You just never know what will happen after you press that shutter button...