In law firms, the key hire is usually an office manager who will wear a number of administrative hats including accounting, payroll, billing, personnel matters, purchasing office supplies, handling vendors, etc. Hiring a strong administrative manager to handle these details can shift 2000 hours of non billable tasks away from the partners and onto a salaried employee. This effectively increases the billing capacity of the firm by 2000 hours. As the firm gets larger, the volume of non billable administrative work might necessitate an administrative department including functional specialists for billing, payables, general accounting, marketing, etc. One reason lawyers have so much trouble with their staff support people is that they are not adroit at hiring.
Most lawyers disdain the hiring process and rush through it just to get it over with.
They hire the first person who comes through the door and seems halfway decent. The result is a bad hire and constant headaches followed by a quick return to the hiring process they hate so much. When hiring staff support personnel, it is important to qualify candidates carefully and talk with a sufficient number of candidates to be able to make a good decision. The process might take longer, but it will decrease the likelihood that you will have to do it again in six months. Success in school is not an accident.