Self-scooping litter box FAIL!

I've been wanting to tell this story, but had to kinda "cool down" and find the humor in it first. I'm there now. So here goes:

I have 4 cats. They poop. A lot. I have 4 litter boxes, strategically placed downstairs so that if they all have to "go" at the same time, they can.
One of these boxes was donated by my parents. It is the Littermaid self-scooping litter box. Here is why they donated it to me: SAM. He is large like a horse and therefore poops like one. The motor in this litter box had to work SO HARD to scoop Sam's stuff that it would actually fling it out onto the floor, where Sam would resume "burying" it in the carpet. I know, funny, right? Oh and I will add that the reason the litter box was upstairs is because Sam was afraid of the basement (where all the litterboxes are). And now you know why his nick-name is Baby Huey.So I have been enjoying the heck outta this litter box. It never flinged poop at my house! Whenl we returned from our cruise, Someone, and I'm not accusing any individual for this may have been a group effort (but I think it was Oscar), pooed SO much on the scooping mechanism that it became plastered in place and the motor burned up. What posseses a cat to poo on the side of something? How is that even possible?
So alas, it was with great sadness that I threw out the unfixable scooper and bought a new box (at 20% off!). And the side pooing has not stopped! In fact, last week someone left a trail from in the box, on the lip of the opening, and then one right in front. What the crap, cats?!?
*sigh*