The client in this example cared about the contents of the top book in the picture, and the original binding was of no importance. Rather than spending approximately $300 for a leather repair of the original binding they opted for a cloth rebinding for about half of that price.
Binders and conservators sometime discuss whether a book is an “artifact” or a “book.” An artifact is a book which has historical value, either because it was your grandmother’s or because it belonged to some prominent person. With an artifact it is important to preserve the character of the binding because of what it says about the previous owner. With a book all that matters is the content.
Almost always, artifacts should never be rebound, unless there is little to be saved. If they are rebound care should be made to keep the original elements of the binding together in a box as can be seen in the conservation photos.
A longer discussion of a book or an artifact can be found here.