There are several reasons why a cat might cry. Here are some possible explanations:
Heat cycle: When a cat is in heat, it may make a "crying" sound, especially a female cat. This is to attract the attention of nearby male cats and seek mating.
Injury or pain: When a cat is injured or feels unwell, it may cry out in pain, expressing its discomfort to its owner and hoping for their attention and care.
Poor mood: Cats may become depressed for various reasons, such as being abandoned by their owners or being punished. In such cases, they may express their dissatisfaction and frustration by crying.

Startled: Cats are generally timid and have very sensitive hearing, making them easily startled. When a cat is startled, it may cry out in fear.
Premonition of impending death: When a cat senses that its life is about to end, it may cry out because it wants to spend more time with its owner.
In addition, tearing in cats may also be related to eye diseases such as glaucoma, conjunctivitis, and keratitis, or it may be caused by environmental stimuli, dietary problems, or congenital genes.