The context is Operating Systems - Critical Section problem. One of the three protocols to solve the critical section problem is Progress:

Progress is : If no process is executing in its critical section and some processes wish to enter their critical sections, then only those processes that are not executing in their remainder section can participate in deciding which will enter its critical section next, and this selection cannot be postponed indefinitely.

Why are the processes deciding which process should go next? Isn't this the job of a scheduling algorithm?