Milord Terms like "a lot" are of course open to interpretation. I should have been more specific - I did not want to claim that it was a majority, or even a significant fraction of people - just that there are more people like that than just a few that are easily dismissed as freak accidents. Of course the majority of people who live fulfilled lives have their physiological need for sex met in some way. Even among asexuals who do not seek out sexual partners, many, but not all, enjoy the occasional relief through masturbation or whatever other mechanism. Many people in the kink community who engage in very long chastity lockups (several months up to multiple years of denying all genital stimulation) still take pleasure from other erogenous zones. And I do not believe that all monks completely cease masturbation when they make their vows. Many might, but others probably just feel more guilty about it than the average person.
Still, there are people who suffer from anorgasmia or genital damage or whatever and thus do not enjoy sex on a physiological level, or who genuinely live without sexual stimulation for extended periods of time and feel happy with that. Maslow acknowledges that when he says the hierarchy is not as rigid as it is sometimes perceived to be.