Why do they make guys get hard before getting circumcised?

My boyfriend got circumcised last week. I went with him, and they made him get undressed completely (which I think is unnecessary). They told him that he had to get hard, he said what? I have to get hard now? How can I get hard like this. The nurse goes, I don’t know your girlfriend is next to you, and if that doesn’t work you always have a phone. I’m standing there WTF, so I told the nurse to leave the room, and I had to get him hard. Has anyone heard of this before?
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+1 y
by the way he is almost 17
Why do they make guys get hard before getting circumcised?
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