If a pharmacist is out due to illness, vacation or other reasons, production slows down and others in the practice will need to either cover for the absent individual, or operations will need to stop altogether, if there are no other active pharmacists on hand to keep things running.
In the latter situation, a pharmacy will lose money due to its commitment to pay the salary of other employees in the organization, such as general managers and store assistants who may be left idle while there are no active pharmacists on hand.