It seems that almost all humans tend to judge art easily and confidently. Without any solid and objective reference, how can they decide boldly and confidently about something that is to a great extent not mathematically rateable?
People say easily and confidently "This person has a very good voice", or "That actor nailed it in his latest movie", etc.
How and why?
More detail:
For example, on talent shows, I see judges confidently talk about the high or mediocre quality of a contestant's performance. In many shows, the performance is not even relevant to the profession and expertise of a judge. Yet he confidently talks about the art piece. So it is mostly (if not only) the judge's personal opinion, and can't be something learned by them or objective. They are merely guessing, yet they are so sure about it.
How and why?
In some cases, it is somehow easier to GUESS if an art piece is good or not. This is the case perhaps in paintings or drawings or an overall impression of a movie, as well as when an art piece is exceptionally unique. But in many other situations, it is really not easy or clear at all to say if this is beautiful or mediocre.
So despite the impossibility of purely objective assessments, how can people decide so certainly about esthetics and art?
ps. Perhaps TV judges are somehow pretending to be so confident because they are on a show. But this pattern is not limited to TV shows. Everybody is like this on and off TV.