So if your weapon does 7-10 dmg, and your enemy has 50 Physical armor (and for simplicity let's assume you are only doing basic attacks) you DON'T KNOW if you're going to need to hit them 5 times or 8 times to take bring their armor below zero!!!!!!
You can however rely on the fact that after 8 successful hits you will get through that armor. You can plan for the worst case scenario. But in case of CC, the worst case is that the CC never applies, and if you are prepared to deal with that, you don't need that CC in the first place and might as well not use it all. If you are not prepared to deal with that, you might just lose the fight because of bad luck, which simply isn't good game design.
