Violet Blue has an interesting take on why men want bigger penises: porn may be the culprit. (Read her blog for a much more in-depth explanation.)
Here are my thoughts. Porn is probably part of the reason. It's not like I want to be in porn, but that I may feel just slightly inadequate compared to the well-endowed porn stars. Therefore in order to feel a little better about myself, I want to increase my penis size to about average. I actually don't want a porn star penis. I want one that's just a little bigger. Having a penis that I'm happy and comfortable with will make me feel more confident about myself. I don't see anything wrong with that because it's not an obsessive compulsion. I'm not saying I want a 9-inch penis.
I'm not at all completely dissatisfied with myself. If these pills can help me achieve that goal of feeling more confident about myself then that's great. If they don't do their job, I would not have lost much other than a few dollars and a little effort--I'd still be OK. My self-image does not depend on the size of my penis.
I think that self-improvement is a good thing. To be completely satisfied with oneself is to be lazy and stagnant. I'm always trying to be a better person emotionally, mentally, and physically. This experiment is just one small aspect in a grander more long-term scheme.
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Now those men out there who are thinking about sizing up your penises, why do you want to do it? And for you women, what's your take on breast implants? Can we even equate penis enlargement with breast augmentation?