To me the idea of taking images has over the last few years changed from a process involving film and chemicals to the digital age that most people now use. Some may say that the photographers of old had a far greater level of skill that digital photographers have or indeed need today. There was no way to check what your images would look like until the films were developed.
In the 1940’s this changed when Dr Edwin Land developed the Polaroid Land Camera.
By checking the instant image produced by the camera photographers could get a reasonable idea of what the image may look like.
Today the importance of checking your equipment (everything seems to run on batteries) and saving images on multiple hard-drives can not be underestimated. In the same way that films could be damaged digital information can be lost/damaged.
The result is still the same :-
THE LOSS OF THE IMAGES , AN ANGRY AND DISAPPOINTED CUSTOMER AND DAMAGE TO YOUR REPUTATION.
By making sure that you look after your kit, checking it before you go to a shoot and backing up your work as you go you can save yourself a lot of problems.
REF BASIC PHOTOGRAPHY GEORGE HUGHES- ISBN 060027252-9