As a client, I could just hire a consultant. There’s no shortage and they have reputation to uphold / less risky to me potentially.
It’s basically the same. I pay hire rate for labor knowing only a portion reaches the laborers. I can select based on the exact expertise I need which consultants would be most appropriate
> As a client, I could just hire a consultant.
True, but in practice large clients can’t be bothered with hiring consultants directly for a number of reasons, so that’s why they go through agencies, basically delegating the entire HR portion.