I;m not a nurse, or even a student yet... this observation is based on my experience as a patient and a volunteer, many years ago, both at an urban teaching hospital.
CNAs existed in theory, but they were never to be seen outside the cafeteria, especially during evening shifts. I don't like bashing, but I am serious... they just were not to be found, and when they were, it seemed the nurses had a hard time getting them to work. I really am not exagerating: as a volunteer I;d ask who was on when I started my shift, and seldom saw any of the 'on' CNAs unless I went to the cafeteria.
Part of the problem, I think, was that this hospital had a huge # of agency nurses, so there seemed to be little sense of obligation towards co-workers since, "hey, either I'm gonna be gone next week or you are".
Is this typical?