Myth, maybe you or both are nervous the first time. I think it’s physically possible , just not emotionally.
Also, the experience of your partner plays into it.
It was with my high school sweetheart. We lost our virginity to each other.
Oral wasn’t the first time but it was always on the menu for both of us. No inhibitions really We got better as we got older lol. I’ve always liked men with beards and mustaches less 5 o’clock shadow and scratchy.