I think Spinks had a combination of things he was dealing with. 1st he was facing the most devastatingly explosive Heavyweight history had ever seen to that point and that guy was in his most peak prime. Knowing that fact presents an ominus opponent to deal with. There's one thing when having caution for facing the toughest opponennt youve ever faced and respecting his prowess. Its another to then know your gonna be facing a crazy streetborn thug motherfucker that woukd just as soon stab you in an alley or kick your ass in a ring in front of millions. By the time Michael Spinks stepped in the ring with Mike, he didnt so much as roll over for Tyson, but he was definitely looking for a way out as soon as the inevitable caught up with him, (which was Mike Tyson hitting him). I think he was worrying about all those other things and didnt bother to really try to compete. He didnt want to be in there, I think he was concerned for his life, because Mike WAS the boogieman. Not to mention, Tyson was so damn good at that moment.
Scare is justy a watered down way to say it. It was so much more than just that..