If you are an experienced photographer then you probably know all of this. But if you’re just starting out, here are some of the rules of professional photography (in no particular order):
There’s no such thing as a simple shoot.
The layout will change after the photo shoot is done.
The CEO always has a bad hair day.
Size of the group to be photographed varies inversely with size of the room.
The only time you need a reshoot is when there’s no time for one.
Gear always works at home. Gear always fails on location.
The chance of a piece of equipment breaking is proportional to its importance for the shoot.
The chance of a memory card failing is proportional to the importance of the images it holds.