Capital ship question regarding abilities

I was just in a battle and it seems like capital ship abilities are not working. Current fight was with Executrix. Basic ability reads "Deal physical damage to target enemy and Expose them for 2 turns". I watched his basic hit 3 times and never got expose to pop. It doesn't say there is a % chance to expose meaning it should happen when the attack makes contact (not including dodge, or forsight I know it negates)
Is this just something I've noticed or is it something that happens to more people.