Why do some bikers wear denim vests?

Why do some bikers wear denim vests?

Denim vests made sense for their versatility and could offer a modicum of protection even in the summer when it was too hot for the rest of the fit but the vests were most iconic when layered over other pieces. The bikers in the above image have layered their denim cuts over deck jackets. Jan 23, 2020

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