The reasons why turtles always close their eyes:

1. The water quality is poor. The water in the turtle basin has not been changed for a long time, and the water quality has deteriorated, causing the turtle to not open its eyes in order to maintain its health.

2. Hibernation. If the ambient temperature is low in winter and the turtle's activity is weak, for example, if the temperature is below 13°C, the turtle's metabolism and activity cycle will weaken, and it will gradually enter a state of hibernation.

3. The weather is hot. If the turtle lies on its stomach and does not like to move when the weather is hot in summer, the turtle's recent eating status, appetite, and mental state are not normal.

4. White eye disease. If the turtle lives in a dirty environment, the turtle will get white eye disease after being infected with bacteria, causing it to be unable to open its eyes.

5. There is a foreign object in the eye. It may be that the turtle accidentally came into contact with some foreign object in the water. If the foreign object enters the eyes, it will also cause the turtle to be unable to open its eyes.