It should get easier with familiarity and it frequently gets harder, for a reason that’s worth naming.
Early on, everything is unknown, so asking is information. After ten years, asking implies that something has been unsatisfactory for ten years and never mentioned — which makes it not a request but a retrospective complaint, and both people hear it that way.
That’s the actual obstacle. Not embarrassment. The accumulated silence.
The other reasons
Not knowing. A great many people can’t answer because they genuinely don’t know, having never been in a position where the question was live. That comes first and it’s a separate piece of work.
Permission. Believing the thing is too much, too strange, or not for someone like you. Usually an old rule rather than a current assessment.
Fear of the answer. A no to a request about sex lands considerably harder than a no about anything else, because of what it seems to be about.
And protecting the other person. Frequently the real reason. Not wanting them to feel they have been failing, which is a kindness that guarantees they continue to.
What makes it land
Not during, and not immediately after. Both are high-stakes moments. A neutral time is considerably easier for everyone.
Additive rather than corrective. “I would love it if we…” rather than “I don’t really like it when you…”. The same information, and one of them is a request and the other is a review.
Specific. “More slowly” and “more of that thing you did” are actionable. “More passion” isn’t, and vague requests reliably produce anxiety rather than change.
Small first. Not the largest item. Something minor, so that both of you get the experience of a request being made and received without incident. That experience is what makes the next one possible.
And name the silence, if it has been long. “I have never said this, and that’s on me rather than on you” removes most of the retrospective sting in one sentence.
Receiving one
Equally important and less discussed.
The instinct on hearing a request is to hear a complaint, and to become defensive or apologetic. Both end the conversation and both teach your partner not to do this again.
What works: treat it as information, and say thank you before you say anything else. You’re allowed to say no to any specific thing. What matters is that the asking remains possible.
Non-verbal routes
For anyone who can’t do this in words yet — and that’s a lot of people — there are intermediate versions. Showing rather than telling. Responding audibly to what you like, which is information without a request attached. Or discussing something at one remove: an article, a scene, a hypothetical.
These aren’t permanent substitutes and they’re a legitimate starting point.
The thing worth knowing
Partners overwhelmingly want to be told. The near-universal report from the receiving side isn’t offence; it’s relief, plus some frustration that it took this long.
The imagined reaction is almost always worse than the actual one, and finding that out is the only thing that changes it.