Floppycats
According to the FDA, perishable food left at room temperature for more than 2 hours should be thrown away.
Feeding your cat wet food that has been out for too long is dangerous because it is a very good medium for the development of bacteria and fungi.
While that’s ultimately up for you to decide, when you leave wet cat food out, even in the 1-4 hour window, the food starts to go bad. After about one hour, the meat begins to dry out, which means that there is little chance that your cat will eat it.