The foot is pretty clean so I would assume that it was made that way and likely sat in a base of some type !! Rather than a vase it could have been a lamp that was disassembled !! Could have been drilled later but really do not think so !! If drilled later it would have been to make a lamp out of it !! Hole discounts any value as a pottery vase !! I would return it to a lamp !! You can buy the parts at a hardware store for about $10.!! Comes in a kit !! Find a nice wooden base for the bottom to sit on !!
Or use it as a vase for dried flowers !!