This situation (interviewing for someone else) is not uncommon in the IT/Software contracting field. Even more common is someone sitting across the room from the interviewee and giving answers. Sometimes through headphones hidden under hair. And I am taking about pre covid times where even if the interview was remote the job was more likely than not in office.
What does the manager do when this happens? I have been there. The answer is simple, I did exactly what I would do if the exact candidate I interviewed showed up but fell short of expectations (say used google extensively, or the questions were theoretical and they were good talkers - happens with QA and Project Manager jobs). If they are borderline, give them a task, see if they are able to complete it. A Manager should do it anyway, interviews are hard. Most companies have probation periods for this reason.
Why does it happen/what’s in it for the candidate/contracting firm?
For the candidate a few weeks or months of experience that they can add to their resume. Do it in 3 or 4 places and suddenly you are a mid level developer. Hopefully they also learn a bit of programming in the meantime.
For the contracting firm any money is money.
Sketchy IT contracting forms routinely do this and worse.
If you use sketchy IT contracting firms, you’re vulnerable to this grift.
It’s pretty common. A contractor attends some degree mill back home and is basically a human terminal. They get some training on how to function and send most of their work to a smart guy who does the work of a dozen contractors.
If you allow remote, it’s 10x worse - the folks are almost certainly working multiple contracts.
I've worked alongside some of the sketchiest of IT contracting firms and I've seen this kind of behavior.
One firm just decided to replace the trained contractors working on my BI team with a bunch of junior devs overnight, no explanation, no warning. The fact that BI management kept employing them says more for the suspected "hello money" I think was paid to get them in first.
What does the manager do when this happens? I have been there. The answer is simple, I did exactly what I would do if the exact candidate I interviewed showed up but fell short of expectations (say used google extensively, or the questions were theoretical and they were good talkers - happens with QA and Project Manager jobs). If they are borderline, give them a task, see if they are able to complete it. A Manager should do it anyway, interviews are hard. Most companies have probation periods for this reason.
Why does it happen/what’s in it for the candidate/contracting firm? For the candidate a few weeks or months of experience that they can add to their resume. Do it in 3 or 4 places and suddenly you are a mid level developer. Hopefully they also learn a bit of programming in the meantime. For the contracting firm any money is money. Sketchy IT contracting forms routinely do this and worse.