This doesn't only apply to Paphs, but nearly all orchids for me. I honestly give up on light-levels and trying to make everything perfect. It makes no sense to me that plants which are supposedly shaded fairly heavily by trees in the rainforest require more light to flower than any other plant I've ever seen in my life. That sounds sarcastic almost, but I'm being quite literal. Ordinary flowers that need "full sun" to bloom do fine in my home, but orchids...God forbid. It's like orchid light standards are a category all on their own, while the rest of the plant world follows normal rules. It gets so aggravating. I just shove them on my windowsill lately and if they like it, fine, if not, I'm not gonna cry.
Maybe "full sun" for a normal bulb or other flower equates to "slightly under favorable Phal light" in Orchid World.