I participated in a team interview a few months back with a candidate who had about 3 years of experience and an outsized opinion of his abilities. Immediately after he had clearly demonstrated that he wasn't as skilled as most people would be with three years of experience, he straight up declared himself to be a "senior software engineer". To experienced, working devs.

My team exhibited an amazing ability to avoid bursting out laughing until he left.

It's reasonably rare, but every so often you get a real gem.