Some dogs, when they are very happy or very excited, make small pees. They do not urinate strictly speaking, but let out a small stream of urine.
A dog that makes a “joy pee” (or excited pee) when you come home is not doing it out of lack of cleanliness or revenge. It is a completely involuntary reflex that we find in dogs who do not know how to regulate their emotions. Any intense emotion in the dog (joy, fear, anxiety, etc.) can lead him to pee with excitement.