Lies are to a not so much meant to deter incurring circumstantial danger, but a fundamental alteration to her internalised reality. Both the fabricated and factual reality coeexisting brings about a state of cognitive dissonance.

Hence why'd she'd also do something superficially absurd as lie during an anonymous survey; this is about supplanting the ugly unforgiving truth within that would unmask her as a base slut lacking any capacity for morality by extraprojecting acceptable confabulations on the matter of her notch count in any scenario that would require them. The actual truth never quite goes away though, always looms over her lies and machinations like a righteous spectre, which is what produces the aforementioned cognitive dissonance. Trying to surpress the truth and both internalise and propagate the lie is a very stressful position with no consistent longterm viability, which is why, commonly, a woman will react with unhinged aggression and instantaneously go on the offense when confronted with any discrepancies in her suspiciously tame numbers.

Point is, a lie to a woman isn't deliberately obfuscating the truth in a specific moment as much as it is alternating their perception of a past event. They can't grasp truth as an abstract, unalienable virtue divorced from individual or collective opinion and instinctively tie it to social dynamics, to which it is subservient and thus malleable if given the opportunity to ameliorate aforementioned social dynamics.

The fact that they downplay their number rather than give an outright implausible if theoretically preferable lie like 'I'm a virgin' is because that generate the most extreme cognitive dissonance; the closer the lie is to the truth the less of a stressor it will be and easier to maintain it both internally and externally. They will lie constantly, in all variations and for every reason imaginable; to stave off conflict, to preserve her social position, to safeguard resources, for personal attention, just to stir up drama because she's bored, to spare herself an awkward moment, to avoid minimal effort ... Lying comes more naturally than breathing to women, even if it's not a long-term tenable position.