Why doesn't Viagra work wonders for me?

I'm a male in the adult entertainment business. I happen to be able to have and maintain an erection just fine during my sexual adventures. However, I keep hearing wonderful, wonderful things about Viagra in the business and how it's the super drug for sex. So I gave it a try (twice), and it didn't work wonders. I mean, I did get an erection, but that's not out of the ordinary. It just wasn't any different than normal. Also, I gave some to my partners as well (both female), and they said they either felt nothing or got warm.

So why doesn't Viagra work like a miracle pill for me?

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