There are many reasons a guy many lose an erection, from simply being tired to something more serious.
Exhaustion
A tired guy can have a hard time getting erect, let alone maintaining one. Get some rest and try again later.
Drunk
Alcohol dulls nerves making it hard for him to get an erection and maintain it, if he's been drinking a lot.
Obese
Being overweight can damage blood vessels, and the way a penis gets hard is all about blood rushing to engorge the shaft.
Smokes
Another thing that damages blood vessels is smoking. If he's a regular smoker, he may find it hard to maintain an erection.
Medication
Some medications can affects hormones in the body, making it hard to get an erection or keep one.
Stress
Stress is an erection killer. When he's stressed, his penis goes back into it's shell like a scared turtle.
I hope this never happen to all of you guys
i just want to share
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