For your example's sake, if the work for one job is just a tenth, then it means that for a 5 men job, a manager would need to hire 50 people. The manager would be overwhelmed and add cost to the company by asking for a colleague. It's not easy to manage 50 people. But maybe the manager wants to diversify himself, so instead of 2 manager for 50 people, you'll have... 20 managers for 50 people. You need a managers' manager. Where does it end? :)