He was setting up for a different shot when he spotted the group of men planting the flag and quickly took a snap without even looking through the viewfinder. The chance photo would become iconic overnight and go on to win the Pulitzer Prize.
The one almost everyone sees is the staged one and the original was never really shown to the public.
It’s a shame that the public has been conned into believing that the popular picture was real. Even the statuary is false!
The 2nd large flag being raised was by no means “faked.” The first was too small to be seen from any distance, and the 2nd went up soon after. It was not some sort of PR stunt with actors. Most of the flag raisers did not survive the war. If you think that qualifies as “fake,” you need to do a little reading on the actual history.