Studies show that lesbian women are more likely to orgasm during sex than heterosexual women.

For men, mean occurrence rate of orgasm did not vary by sexual orientation: heterosexual men 85.5%, gay men 84.7%, bisexual men 77.6% (F2,1494 = 2.67, P = 0.07, η2 = 0.004). For women, however, mean occurrence rate of orgasm varied significantly by sexual orientation: heterosexual women 61.6%, lesbian women 74.7%, bisexual women 58.0% (F2,1350 = 10.95, P < 0.001, η2 = 0.02). Lesbian women had a significantly higher probability of orgasm than did either heterosexual or bisexual women (P < 0.05).

https://onlinelibrary.wiley.com/doi/abs/10.1111/jsm.12669

Heterosexual men were most likely to say they usually-always orgasmed when sexually intimate (95%), followed by gay men (89%), bisexual men (88%), lesbian women (86%), bisexual women (66%), and heterosexual women (65%).

https://link.springer.com/article/10.1007/s10508-017-0939-z

But does this mean that lesbian women experience more often sex with orgasm than heterosexual women even in absolute numbers? Studies show that lesbian couples have sex less often than heterosexual couples. This is particularly evident in long-term relationships.

Among couples in the first two years of their relationships, 67 percent of gay couples, 45 percent of heterosexual couples, and 33 percent of lesbian couples had sex three times a week or more. The numbers drop off somewhat with time: for couples who had been together 10 years or longer, 11 percent of the gay couples, 18 percent of the heterosexual couples, and 1 percent of the lesbian couples were having sex that often.

https://www.psychologytoday.com/sg/blog/the-passion-paradox/201206/the-ins-and-outs-sexual-frequency

Compared to heterosexuals, lesbians were more likely to report having sex 0–1 times per month (11% vs. 23%) and were less likely to report having sex greater than once per month (89% vs. 77%). Among women who had been in **relationships for longer than 5 years, heterosexual women were less likely than lesbian women to report having sex 0–1 times per month (15%; 42%).

https://pubmed.ncbi.nlm.nih.gov/34725751/

Frequency of sex was lower among lesbian women than heterosexual women who had been together for longer than 5 years. For example, fewer heterosexual woman than heterosexual women reported having sex 0 times per month (0% vs. 3%), 0.5 times per month (7% vs. 22%), or once per month (8% vs. 17%)

https://www.researchgate.net/figure/Frequency-of-sex-was-lower-among-lesbian-women-than-heterosexual-women-who-had-been_fig1_355834363

I recalculated the percentages in the last study to a group of 1000 women in relationships longer than 5 years:
Lesbian women: 2,760 sexual activities per month.
Heterosexual women: 4,295 sexual activities per month.

With a probability of orgasm of 65% for straight women and 86% for lesbian women, this makes for one average woman:

Lesbian woman: 2.4 sexual experiences with orgasm per month.
Heterosexual woman: 2.8 sexual experiences with orgasm per month.

Why is it written everywhere that lesbian women have more orgasms than heterosexual women?