How to evaluate the quality of a calligraphy?

All works of art have a judging phenomenon of "different people have different opinions". For example, Song Zhenzong Evonne is good at "thin gold body". Some people say that his calligraphy is good, while others say that he is weak.

Generally speaking, there are still some general standards to evaluate the quality of a calligraphy:

1, it seems that people are not uncomfortable and have a sense of pleasure.

2, it seems that people are not blocked and have a sense of fluency.

3, it seems to have the change of ink color and three-dimensional sense.