if speaking from a merely sexual perspective, then no, an orgasm is never impossible.
Sadly, there are far more factors. If a girl isn't mentally comfortable with what's going on, the likelihood of reaching orgasm reaches darn near nil. Another example I've found (and heard) is that if a girl feels self-conscious, especially about her physique, you're fighting a losing battle if you want to make her cum.
she's got to feel beautiful, flaws and all, and she has to be comfortable with herself and the situation.
Sadly, there are far more factors. If a girl isn't mentally comfortable with what's going on, the likelihood of reaching orgasm reaches darn near nil. Another example I've found (and heard) is that if a girl feels self-conscious, especially about her physique, you're fighting a losing battle if you want to make her cum.
she's got to feel beautiful, flaws and all, and she has to be comfortable with herself and the situation.