The mere comparison of strength between the two characters is crazy. Goku is an extraterrestrial being who has to lose a fight in order to get stronger. Saitama is a man that can defeat any foe with a single punch. If the two of them were to face off in a one-on-one battle, who would actually win? That's the real question.
Saitama clearly has enough battle IQ to win as often as he does throughout One Punch Man, even in the battles that take more than one punch. However, only having to throw one punch most of the time doesn’t exactly keep one's battle senses and intelligence sharp. Goku, on the other hand, is always in situations where his battle IQ is being heightened. Nearly every fight we see Goku in, he has to push beyond his limits to overcome his opponent.