At some point, the question becomes: was the candidate too unqualified to understand what they were applying for?
I don't mind training someone if they're not 100% up to speed but they also need to be capable of learning and retaining things. A lot of that means that you need a foundation based on education and on the job learning. In other words, I'm not going to teach foundational shit that you should have picked up in high school.
One memorable example: we had one applicant who claimed a high degree of competence and related experience - and although I had some doubts during the interview I was realistic about the job market and our chances of finding someone who was a perfect match. She was personable, seemed smart, and had worked in the industry. How hard would it be to train her? If she could manage to pick up even the most basic parts of the workload it would be win to hire her.
A short list of what we learned
I'm going to gloss over a lot of irrelevant (but horrifying) detail here. We did have one memorable conversation where she said, "I'm so glad I applied for this job even though I wasn't qualified. You never know where you can get by trying!"
Where she eventually got was fired, but that took some time and the damage she did is still legendary. Part of that legacy of raging incompetence is that we fact-check resumes in ways that we previously did not. But the great irony is that she probably had no idea of just how unqualified she actually was. Again, the question becomes: is the candidate too unqualified to understand what they were applying for?