And it was probably extra tough to find a donor whose equipment matched that of the recipient's original. Imagine you're one of those guys whose urine stream tends to flow a bit leftward, and you've spent a lifetime automatically making that little rightward adjustment. Then if they replace your original unit with one that pees to the right you're gonna wind up pissing on the floor every time. You'll have to carry a mop around with you for the rest of your life.