What are the common reasons given for not using an insulin pump and cgm?

Patient preference: People with diabetes who use an Insulin pump along with continuous glucose monitoring (cgm) do get better control of blood sugar levels, which dramatically reduces the long term diabetes complications, and slightly increases episodes of too low blood sugar. It may not be as helpful for those at high risk of low blood sugar, or for those who wish to minimize treatment and forego long-term benefits.

Several: Deciding to use a pump with or without cgm is a personal decision. Some reasons it may not be right might include increased cost, complexity, not wanting to be dependent on a machine, very active lifestyle, self-consciousness, or not wanting to test as often as expected with a pump or cgm. It's a great choice for many patients, but not for everyone.