I think men lie because they feel insecure about needing to meet some minimum requirement to be perceived as manly, verily, adequate. All the attention to, and hype about, size makes this problem worse. Perhaps they have experienced size discrimination in the past but even if they haven't the bigger is better message is pervasive. Hence the insecurity and perceived need to lie.
One other point... You may get away with lying to someone you will never be intimate with but lying to a potential partner makes no sense to me. I would be more ashamed of lying than of my size when the truth becomes known.
I wouldn't lie about my size. At 5.7 x 4.9, if I was asked, i would say I am about average. If I was asked to be more specific I would be truthful.
I suspect most women, those that were asking in the first place, would respect that honesty. After that, they are fully entitled to their preferences so I then need to respect them if my size is a deal-breaker. I suspect, or at least hope, being a deal-breaker would not happen often.
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