I had one of those "spot the issues" quizzes on an interview once. I didn't do that well on it just because I was nervous as hell. In retrospect, it was a good thing they didn't want to hire me. But it was a dumb request to place on someone "hey look at this class from our codebase and tell us what's wrong with it!" I'm thinking: "Should I just praise how good it is? What are they asking me here?"
> I didn't do that well on it just because I was nervous as hell.
The problem is everyone gets nervous. The only way to avoid that is paid work trials and to decide whether you want to keep hem after 90 days. But that requires the person to quit their job.
> "hey look at this class from our codebase and tell us what's wrong with it!"
Ours is a self contained example, littered with absolutely obvious errors that anyone who has written the language being interviewed for (C++) should be able to spot a least 2-3 issues with. There are absolute glaring fundamental issues in about 50 lines of code and you are explicitly told there are numerous errors with it.