Why does calligraphy have bright eyes?

This is the so-called "post-writing", for example, the diligent word has less horizontal at the lower left, the Liang word has less horizontal at the upper right, and the Beijing word has a horizontal at the mouth. This is what friends who study calligraphy often see when practicing posts.

This way of writing is not right or wrong: Chinese characters are all handwritten in the era when there is no "print", so handwriting is naturally more casual, just like running script and cursive script, no one will care which word is less horizontal and more vertical; And there are personal habits. Of course, today we should advocate the standard use of Chinese characters, especially the strict requirements for teaching children to write. If the word "Ming" is written as "Muyue", it will be considered as a "typo".