Why does everyone who has an amputation not get an artificial limb?

Early or non healing. It could be early after the amputation or there is a problem with stump healing, infection , not fitting. Sometimes very weak patients also can't get an artificial leg .
Many possibilities. 1. Patients with an open surgical stump 2. Patients who are unable to ambulate due to severe ballance impairment. 3. Severely weak patients who would not be able to walk.