Telling someone exactly “I’ve never given a woman an orgasm, likely due to my shockingly small penis” is a perfectly fine thing to say if that’s being honest, even if it’s not accurate. However when you choose to say it matters, there’s context for something like that to come up, anytime sex is injected into a conversation needs some kind of context before it’s acceptable, unless you are comfortable with just blind luck to provide a positive reaction.

Which can happen, but it’s rather poor chances