There are actually several groups. This site is particularly concerned with what here will be called true wannabes. These are individuals with an amputation wish that is not primarily sexual in its origin. For some amputation will be the best solution. Others will choose therapy but first they must be allowed to choose.
The second group consists of people with a predominantly sexual motivation for amputation. These are individuals that often change their minds about kind and level of amputation. Such a person is likely to regret an actual amputation.
In the third group you find what can be referred to as the psychopaths. They can be people who believe that the limb they want amputated is in some way or another "evil". Someone may blame their inability to stop stealing on the hand and therefore cut it off. Amputation can in this case not be considered a solution or "cure".
The fourth group includes the dependence seekers. They seek amputation as a means to have people care for them.
The last group consists of people who have injured a limb or have a limb which is affected by disease and whose life will be improved by amputation although it is not really necessary. These people are those that are most well met by hospitals and surgeons.
Please note that these groups do not have any sharp borders and that any of these people in addition also can be a pretender (a person pretending to be an amputee by tying up his or her legs, arms, use a wheelchair etc.) or a devotee (a person who is sexually attracted to amputees/persons with a disability). One does not preclude the other.