Why is jealousy unattractive in a guy?

I've noticed that it seems jealousy, while it can be unattractive in both sexes, is more unattractive when a guy does it. What uniquely makes male jealousy, even in small, benign amounts, such a turn off?

Why is jealousy unattractive in a guy?
Why is jealousy unattractive in a guy?
It just makes me feel unsafe
It makes me think less of him, because he thinks less of himself
I'm afraid he'll fight over me and/or ruin my friendships
It makes him less stoic and masculine
I don't find it unattractive
Other (explain, you know the drill)
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+1 y
Let's say you are on a date and tell your boyfriend about a new best friend you have. It's a male you work with at a job you started a few months ago. He'd heard you mention him more than a few times on dates and on the phone, but just didn't who exactly he was or what he means to you. So then your boyfriend feels a bit jealous. He makes a playfully sarcastic and competitive, but self deprecating joke in relation to your best friend. How would you rate his unattractiveness in that moment?
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+1 y
didn't *know* who exactly he was
Why is jealousy unattractive in a guy?
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