Jobs where people's lives are at stake? Require Focus surgeon, for example, cannot be preoccupied while doing a heart bypass or , or he may end up killing the patient.
Those that deal with National Security should also be people who can zero in on important matters.
Home.
If a Federal Officer Wants To Catch a Criminal, they have to keep an eye out for him.
I think work that has a deadline will also need undivided attention.
Anything that requires mindfulness will take away your time and that leads to cramming or failure to meet expectations.