The whole model is based on the 10 grunts only costing as much as 2
Then you have the outsourcer's profit of 3 head count, plus whatever they can get from maximising head count utilisation across customers, 3 for the client to justify the outsource.
So they're underqualified/experienced, overworked/slower to respond, less familiar with the IT estate and usually remote. All to save the equivalent of 25-40%*. It's a great deal, if you only look at the costs. People buy the hype that they can get the same level of service.
*Not a guarantee. Performance and costs may vary over time. Historic charges are not an indication of future expenditures.