[kaftoy]

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? :)

[Grimm1]

I think they're implying that the majority of current working time isn't actually work, that those jobs could be done with 1/10th the current man hours and still be just as productive.

In that world you don't need to hire anyone else because all you've done is cut back all the bs idling time that we all know exists in many jobs while keeping output the same.

FWIW I'm not sure I agree on the 1/10th but like 1/3rd or 1/2 absolutely from my position.