If you had to project a user interface onto the surface of vegetables, no doubt you would find that variety isn't your friend. The user interface that has a lot

If you had to project a user interface onto the surface of vegetables, no doubt you would find that variety isn't your friend. The user interface that has a lot of detail and works great on a 4kg squash is going to be impossible to see on a radish and, because there are many, many sizes inbetween, you end up with perhaps dozens of levels of detail to design for with many quirks if you're not super-careful. Meanwhile, some fruit company chooses to only accept a handful of fruit sizes: an apple in two lengths, and two sizes of watermelon. Your job of projecting a user interface onto those surfaces is an order of magnitude easier because you're really only dealing with a couple of levels of detail to design for.