Some work has to be done to meet a schedule or contract requirement and that must be done first.
Sometimes the employee doesn't know which of two "gotta be done jobs" should be done first - that requires a supervisory input
A basic rule is that an employee should be moving the load forward all the time. If work has to sit while waiting for a rely (for example) smaller jobs can be done to fill up the time.
Multitasking does not work. Do a job well not two jobs poorly.
Work which is not your job gets moved off your desk and onto the proper individual's desk.
Work assignments must be described fully not allowed to grow after assignment
