why do the male cat always out of home?

Every cat is different but if your male cat hasn't had the snip he could be on the hunt for a female to mate with. There might be a new male cat(tom)in the area and your cat has been busy remarking his territory. If your cat is normally at home and now he is away look at your surroundings you may of changed something or are doing something different. Cats don't like change and they can get stressed. Your cat could just be independent and prefer to be away from the house. Best to keep an eye on the situation and if your cat hasn't been snipped, it might be best to call the vet and see what they recommend.