Occasionally I noticed that when my garage door is open, stray cats come and sit under the car. It could be because they like the warmth under the engine compared to the coldness of outside. I don't mind it because it winter is cold.
The problem is that when I close the garage door at night, sometimes a cat stays in and is locked for the whole night. I do check and try to hush out the cats, but it is not always possible or feasible to thoroughly check. There isn't any food or other things which can be attracted to cats. What happens is that I've to clean and wash the garage the next day because the cats have used the garage as their toilet.
How can make sure that cats are not trapped inside my garage?