Have you ever had someone draw attention to your failings? Has anyone ever highlighted them in fluorescent yellow making them more visible than they were before? If so how did you take it? Were you upset, annoyed, embarrassed? Mostly I think people don't like having their failings highlighted although in reality is it not a good thing?
Imagine a person plodding along in life doing things a particular way, maybe not the best way, but in a manner that works. Then along comes someone who objectively observes the other, points out some improvements and makes life a whole lot easier for the other person. How could that be bad?
I believe constructive criticism and evaluation is not a bad thing at all and am always pleased to receive it. Sure, it needs to be delivered in the correct manner however if that's done I always find it to be of value. I'm open to learning, adapting and improving. Many are not, but fortunately it works for me. Unsolicited advice on the other hand is not as well received.
I think it's interesting how constructive input and unsolicited advice run parallel and depending on the delivery can be generally, even gladly, accepted or can indeed be received poorly. Either way though, I believe highlighting one's good and bad points, success and failure and areas for improvement, re-training or elimination in oneself can assist in a person's life-journey deepening and broadening the possible results and outcomes.