Solutions that feature extra levels of pointing naturally arise in many cases. E.g. you search some data structure for an element. Initially you may do this so

Solutions that feature extra levels of pointing naturally arise in many cases. E.g. you search some data structure for an element. Initially you may do this so that the search returns the element itself or NULL if it's not found, but then you realize you'll also need to use the same searching logic to insert and delete elements. In this light you rewrite the search to return a pointer to the location instead; this way you can use it as a subroutine for all the operations.