What does “having sex” mean to you? If you’re a gay or bisexual man, chances are that you define it as insertive or receptive anal intercourse, or “topping” and “bottoming,” respectively, as they’re known more commonly in the community.

Men who have sex with men tend to see this as the “gold standard” for sex, according to scientific research. In a 2017 study published in The Journal of Sex Research, participants were recruited at Pride festivals to complete a survey about their definitions of sex. Specifically, they were asked to evaluate up to 17 different activities and determine whether each one counted or not.

While there wasn’t 100% agreement on anything, gay and bisexual men mostly agreed that anal intercourse counts—in fact, more than 90% said that “topping” and “bottoming” were “definitely sex.”

No other activity on the list was categorized as such by a majority of participants. For example, approximately one-third said that oral sex, rimming, using sex toys with a partner, and mutual masturbation could be considered sex.

By contrast, lesbian and bisexual women saw things very differently. In fact, there were ten different activities that a majority of them said were “definitely sex.” These activities included using dildos, oral sex, sixty-nining, rubbing vulvas together, and mutual masturbation.

Gay and bisexual men, it seems, define “sex” in a far more restricted way than do lesbian and bisexual women. Moreover, most gay and bi men identify as strictly “top” or “bottom” when it comes to sex. A 2017 study published in the journal PLOS ONE found that, among gay men, more than two-thirds (69%) identified with one of these position labels.

So, what are the implications of the fact that gay and bisexual men tend to see sex in such narrow terms and, further, that most identify with a specific sexual role? Is it a good idea to take such a black-and-white approach to sex? As a sex researcher and educator, I see it as being more harmful than beneficial for several reasons, which I explain below.

Narrow definitions of sex lead to a scripted, goal-oriented approach to sexual activity.

When sex is defined very narrowly, this necessarily sets a goal for a given sexual encounter. People try to get through everything else—the foreplay—quickly (or they skip it altogether) in order to reach the “main event” where everyone has their clearly defined roles.

If the pioneering research of Masters and Johnson—the founders of the modern sex therapy movement—taught us anything, it’s that goal-oriented sex doesn’t make for the best sex. In fact, it creates a sense of pressure that forces you to stay in your head and stick to the script rather than getting lost in the moment, having fun, and exploring different sensations.

In other words, sex is no longer about what you want to happen, but what you think is “supposed” to happen. The result is that sex has a tendency to become routine very quickly. Further, pressure to stick to the script can create performance anxiety that reduces sexual desire and arousal.

You would probably be surprised at the number of gay men who have approached me over the years who want my help because they’re in sexless relationships. They’re having sex with their partners infrequently or not at all—and do you know why? It’s almost invariably because their sex life has become too predictable: it’s the same thing over and over.

Rather than trying to mix things up with their current partner, many of them had cheated, some had opened their relationships, and some were thinking about breaking up. However, these things aren’t necessarily going to solve their underlying issue—the predictability of sex. Those who just break up are dooming themselves to experience the same problem time and again because, well, “same script, different cast,” as Whitney Houston and Deborah Cox once told us.