Reasons for excessive eye discharge in cats:
1. Nasolacrimal duct obstruction caused by dacryocystitis leads to yellowish-brown or milky-white secretions in the corners or around the eyes.
2. A large amount of discharge caused by feline rhinotracheitis in cats will accumulate in the corners of their eyes. 
3. External injuries can cause eye damage, resulting in dark red, jelly-like or yellow discharge from the corners of the eyes.
4. Cats may experience excessive eye discharge due to dehydration caused by not drinking enough water.
5. Due to differences in cat breeds, some cats have flatter faces and shorter nasal passages, making them more prone to eye discharge and the formation of a lot of eye boogers.
