From my experience this is just one of those things where you have to make mental notes. Some character skills just naturally have more initiative, from what it seems. Typically interrupts are the highest, followed by defensive skills and then supportive ones. It makes sense because all of these, in theory, would be something someone does preemptively to mitigate damage from an opponent. I'm not saying it's universal truth but it's what I've seen in my two months and logic makes sense.