Where do most young guys get their OVER confidence?

Im at bit odd here because I'm someone who HAD to prove his worth & "ego" growing up

I did a mix of mma & powerlifting in my late teens & I did have a few win streaks here & there

I'm the nerdiest guy you would see in the streets but my former skills spoke for themselves

I'm just curious because alota dudes who are either too overweight, shorter than me, have never competed in anything nor won either act very arrogant in general

Towards me as well UNTIL they see what I USED to do

But I'm just curious where guys get their big egos?

Where do most young guys get their OVER confidence?
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