I wasn’t a part of the interview process, but I was told some of the details. The interview was remote and they did well on the video interview and on the take home challenge. My best guess is they were being given help.
My company hired a senior developer for an Angular project we were working on. They did great in the interviews and on our take home coding challenge. When it got down to time to work, I was walking them through the codebase and it very quickly became apparent they not only didn't know Angular, they didn't even know much at all about web development in general. They were let go three days later. I'd heard of things like this happening but I couldn't believe it until I saw it in real life. I just can't imagine what someone like that is thinking. I get "fake it 'til you make it" but this was on a whole other level.
One of the companies I interviewed with did what he described and it was nice. I thought the cool thing was that in the second interview they wanted me to walk them through some of my thought process for why I did/searched for certain things.
I didn't end up taking the job, but boy was it a breath of fresh air compared to some of the other interviews I've done.
I've never seen it happen in person either. As someone who used to be terrified of going to the gym because I didn't want to look like the new person at the gym, I can say for myself that it was all in my head.
"..you will become way less concerned with what other people think of you when you realize how seldom they do." - David Foster Wallace
I enjoyed this article. Especially his discussion of writing filler text in scripts that would be ironed out later during rewrites. I see a nice correlation to writing software. Get it working in general and then go back and optimize it.