I genuinely don't even understand it. I was either taught wrong, learned wrong or this doesn't make sense. O(100) is constant time, so it's no different to sayi

I genuinely don't even understand it. I was either taught wrong, learned wrong or this doesn't make sense. O(100) is constant time, so it's no different to saying O(1) or whatever, I've only ever used O to talk about how we care about the time complexity of a function, e.g. comparing linear time to quadratic time. 1 is the same as 100, irrelevant.