Well lets see one of the worst fuck ups for me probs happened about 5 times luckily is when I spend about half an hour having a rock solid hard on during foreplay that when it came to the sex it just wouldnt fucking stay up thats why sometimes the old blue pill does the job haha always makes your sex a hell of a lot better and lasts for a minimum of 3 hours which is good, nothing embarrasing about it its not just for old people and any girl will absolutely fall in love with you for it .