It’s not about having an obective answer to your pain levels, that’s impossible since everybody experiences pain differently.
I worked in the hospital for some time and it was my task to protocol those pain tables every day.
At least where I worked the point of it was to have visualisation of the patients pain development over time.
For example patients comes in and gives a 8 on the scale. He gets an operation and gives a 6 afterwards, after a week he gives a 5 but in the next week he gives 7 again - this development could tell us something about the healing process, maybe there’s an infection that would’ve slipped by if we didn’t see this unusual rise in pain levels.
Yeah I wasn’t answering to your anecdote, just trying to illuminate the purpose of those charts and that their rating is inherently subjective.
Obviously being dismissive about it is not productive.
Although there were times where we asked patients to reassess them, almost always when their answers were in the high end of the scale, a dude sitting totally chill drinking tea answering ‘10’ is not really believable and could cloud what’s happening. I mostly described it as “1 being a mild inconvenience and 10 being the strongest pain you have ever felt in your life”