There's often something that pet owners don't consider when they get a pet, especially if they have multiple pets. Cleaning! Pets can be loving, fun, interesting companions, but they can't pick up after themselves. Which means that we the owners get to do that. And yes, I had a big day of doing that today, which is why this came to mind.
Today I had to clean a betta tank, remove and replace bedding in a rat tank, clean the cats' litter box, and clean out the bearded dragon tank. Doing all of that took me the better part of an hour, and wasn't the most pleasant work. However, in the mini-zoo we have in our house it's a necessity and one you can only put off for so long before conditions get unhealthy.
I'm not sure many people consider this less-than-pleasant aspect of having animals in the home. You have to clean up waste, keep them clean (I had to give my beardie a bath today), and pick up messes that they may make with chewing and scratching around the house. Pets are still less maintenance than children, but they aren't completely maintenance-free. This is especially true with caged pets such as birds, rodents, and reptiles where you have an enclosure that must be cleaned and you can't train them to eliminate in a specific place.
Still, it's an acceptable trade-off as far as I'm concerned, and the price we pay to have the joy of pets around us.