There are a variety of reasons why pet owners seek to give up their pets. I think I've heard most of them and though most are ridiculous and frankly, really come down to a sense of laziness and unwillingness to do the work on the part of the owners, some seem downright reasonable. Case in point – cats that insist on defecating outside their litter boxes.
It's hardly delightful to live in a house of land mines. And when your cat is refusing to use their litter box, that's what your house begins to feel like. Anywhere in your home becomes concerning – random places in the floor, furniture, beds and laundry baskets all must now be explored timidly. But poop isn't the same as spraying. Spraying is about territory and marking, it's about your cat screeching the word "MINE!!!!" with urine. Poop outside the litter box comes down to only one of two things – their litter box has been deemed unacceptable or they have a major preference for their new bathroom location.
But why? It doesn't make sense. At this stage the litter box has inevitably become a thing of luxury. It's the upgraded, Cadillac sized box filled with the softest, finest grain litter available, that is monitored diligently and scooped with a regularity that has you holding your breath waiting for the sound of scratching. But it could be a couple easy things – maybe the litter isn't deep enough for kitty to be comfortable digging (2-3 inches is ideal), the box could be too small (it should be almost 2 times the length of your cat ideally), the litter could be overly scented (unscented is best for kitty's sensitive sniffer), the litter could be too rough (scoop able, fine grain litter is best), the box could be too closed in or small for your cat or it could be too dirty.
Observing your cat can help answer the question as to why. If your cat is hesitant to climb into the box, it could be too small or too dirty. If your cat races out of the box and leaves their poop uncovered, they could have an issue with the texture or quantity of the litter. Personally, this is where I tried what I like to call "the Litter Lottery". I bought 4 different style boxes and 4 different types of litter and lined them up in our guest bathroom. Unfortunately for me, my cats preference was for the litter we were already using and the box style we were already using. Typically though, within a few days, your cat will demonstrate their preference for litter and a box. Jackpot! That's the litter and box style you want to choose. This process may include switching box styles with different litters to best accommodate your cat or it may be an easy obvious first choice.
As it became apparent that the litter and box style wasn't the issue for our cat, we had to begin looking at the environment and location of the litter box. The location of the litter box should be somewhere quiet, where loud and sudden noises are unlikely to occur. Laundry rooms are a horrible idea. Just one loud sound and kitty could forever write off that litter box as terrifying and evil, and thus, avoid it. Kitty's food cannot be located near their box. Though a cat room sounds appealing, no one wants to poop where they eat and kitty is no exception. Move the food bowls further from the litter box location. Convenience is also a factor. You want to make sure the litter box is in an easily acceptable location that isn't blocked by other animals or children in your home. If your cat has to navigate through screaming, running children or another aggressive cat or dog to get to their box, they may avoid it in favor of an easier location, like your sofa.
Regardless of the reason your cat began avoiding the box, in order to get them to commit to using it again, you have to make their new locations undesirable. You want those new bathrooms to scream "ABSOLUTELY NOT A BATHROOM!!". First you have to clean every single area that kitty has used as a toilet. An enzymatic cleaner is essential. I like Kennel-Sol, though it's expensive and has to be ordered online. But Simple Solution and other cleaners are available at your local pet stores. Next, make the cleaned area unaccessible. Close the room, cover the spot with aluminum foil or an upside down desk chair mat with little plastic spikes or even place your cats food bowls there. I chose to use a Scat Mat. This mat is an electrostatic charged plastic mat that delivers a small shock when it's touched. Kind of sends the keep away message loud and clear I think.
Defecating outside the litter box is a habit and like all habits, will take time to break. One option is to limit the areas in your home that the cat can visit unsupervised until they grasp the litter box idea. Another is to reward the use of the litter box. At one point, the sound of scratching in the box would bring me sprinting up the stairs with kitty Greenies (his favorite) to reward him coming out of the box. It takes time and effort, but cats can be retrained and find happiness in your home again.