laevigatum is not variegated!
Not sure about the exact meaning of the species name, but botanically Paph. laevigatum is a synonym of Paph. philippinense. In horticulture the name is often used for a specific type of Paph. philippinense, mostly with broad leaves and rather spread-out petals.
In my plants I've noticed what the others said, leaf markings/variegation is often not pronounced, mostly reversible and most often nutrition linked. I have also achieved some nice contrasting leaf marks with the misapplication of a fungizide, though.
G..... tells me there are different forms of Paph insigne with variegated leaves and propably the odd other species, too. I know this occured on Phrags, too.