I need more information. What unit do you work on? Med/surg, long term care, peds, etc? What is the nurse to patient ratio? Does your unit have a lot of admits and discharges each shift? What shift are you working?
What duties does the charge nurse have? Assign new admits, assign lunch breaks, monitor new nurses? Arrange and plan staffing for the next shift? Review policies and procedures, attend meetings, do staff evaluations?
Is it accepted, expected, that as charge you take fewer patients, or take stable patients?
I've worked units where the charge nurse was out on the floor every day, helping out, taking patients, etc. Her replacement was seldom seen, spent most of the shift in the office. I don't know if in the first scenario the charge nurse was not completing assignments, duties, her bosses expected of her and in the second scenario the charge nurse was playing catch up? Or the second scenario the charge nurse was finding excuses to not be on the floor?