The photographer will retain artistic rights to edit to their own high standards and choose the images which are fit for use. Prospective future customers will judge the photographer on the work they can see so this is of vital importance to the photographer. Retaining copyright means that the photographer can't be compelled to release images before they are finished, and can safely hide away the test shots and ones ruined by people looking away, or walking in front of the camera. It also allows them to place restrictions on how the photographs that have been released can be edited, to ensure that someone doesn’t do a botch job at a later date leaving poor quality images credited to them. With the advent of apps such as Instagram, it is easy for anyone to take an image and apply a trendy filter to it. However for a professional photographer, being associated with these type of images is anathema, makes them look like amateurs and trend-followers and can put other customers off.

Still on the theme of ensuring that work they have done brings in new work is the right to be identified as the creator. This does not mean that they must be credited everywhere the work is used (though in setting out a licence they may stipulate some circumstances where they must be credited), but it does mean that nobody else can pass the work off as being their own. There are moral rights which exist in extreme cases of misattribution, but these are costly and difficult to enforce and only apply when the photographs are explicitly stated to have been taken by someone else, they can't protect the photographer's interests from uses which mislead and imply that someone else is the creator.

The copyright holder has the exclusive economic right to receive payment for the use of the photographs. What this means is if another company approaches you and says they would be keen to use the photographs, assuming you have given permission, that company will then have to approach the photographer and in most cases pay a fee for a licence to use the images. This is an important secondary source of income for most photographers, without which they would be left with no option but to put up prices across the board.

With copyright also comes responsibility as a photographer's professional reputation rests on the images and how they are used. If a third-party were to use the images without permission, pass them off as being their own work, or modify them in a way that degrades the quality the the photographer will wish to pursue that person through the legal system; something which is tricky for them to do if the copyright is held by a third party (such as yourself).

Had the copyright been transferred to yourself and this happened (and it does happen) then you might be placed in an awkward position; receiving a letter from your photographer pleading with you to support their legal action against the perpetrator.