He manages to pull off what are otherwise known as fashion no-nos. Take the above picture, for example: by tying a sweater around his neck and wearing a denim jacket, it seems as if he's confused by what he wants his outfit to say. Does he want to come across as a yuppie? Or as a tough guy? In addition, both elements are way too big and bulky for his petite frame, adding visual weight instead of reducing it.
Yet he pulls it off! Let's be honest here: it's Steve Perry, he can wear whatever the fuck he wants. Who the hell are we to question his choice in clothes? After all, nothing he wears is a mistake. He chooses his outfits with the precision of a sniper going after a target. He wants to send out mixed signals. He wants to keep us guessing. He refuses to be pigeonholed into a stereotype. It's like he's saying, "Try to guess. I dare ya." He doesn't want us to know what his body really looks like, if only for the sake of surprise. Wearing bulky outfits like this one gives him the freedom to bust out in his signature leotard/tight jeans or tight jeans/leather jacket/no shirt combos, thus surprising (and simultaneously turning on) his audience.
Steve knows what's up. He's nobody's fool.