I will also add, from the perspective of the appliance designers, that the patients that are given insulin pumps are the ones that are incapable of managing their glucose levels through more traditional means (portable glucometers and testing strips). This isn't always behavioral but it's... often behavioral.
If there's a hole in you? Through which foreign substances pass with regularity? You are not in a good way. Medical professionals usually save the cybernetic implants until you'd be dead without them.