Because I'm pretty sure if I owned one, it would become mentally incapacitated the minute I brought it into my house. I really think that every animal I have owned has had some sort of mental issue.
Crystal's Animal Case Study:
Mickey - I got this cat from my mom. She was the tamest of the litter. Maybe it was the 3.5 hour car ride home with Mark & myself that ruined her. Or perhaps it was Mike using her as a dust mop and then trying to microwave her (I assure you, coded the child lock on the microwave before he even arrived. We were still college students, afterall.) Now, I only have fond, sweet memories of my little beloved Mickey. However, friends and family members called her Satan, Evil, Devil Spawn, and a host of other less-than-affectionate names. Sure, she pretty much attacked anyone that walked through the door, but she slept curled up in my arms every night. She loved me. But she clearly had some issues. She was an indoor/outdoor cat. Never fixed. Never pregnant. Some said she was too evil to reproduce.
Of course, I thought, well, maybe I just got a weird cat.
Mickey disappeared while I was on a trip to Key West. I have my suspicions that someone came into my house while I was gone and let her out, but we'll save that one for another day. Regardless, after loving her for 12 years, I never saw her again.
A few months later, I was ready for a new kitty. I went to the rescue shelter looking for a white kitten. They had a pure white cat, but it was a little older than I was looking for. I fell in love with a white cat with black markings. I wanted to name him "Phantom" (because he has a black marking on his face), but I let the kids choose his name, "Oreo" (they were pretty little...there's way more white than black...but I digress). Anyway, he's a pretty good cat. He's not nearly as evil. But he does have an evil streak. He'll tear your arm off if you pull your sleeve down and show it to him. (Of course, I did teach him that trick). But, he's still kinda weird.
We tried to get a dog a few years ago. Her name was Patch. She may honestly have been the dumbest dog on the planet. Now, I don't know if she was that way before I got her, but she certainly was once I had her. I passed her on to a family that was more patient in dealing with dumb.
We decided another cat would probably fit our family better. (Fia Sloth had just been born). We went back to the shelter where I adopted Oreo. Sasha picked us out. She was a beautiful grey and fluffy kitten. And she was ohmygoshsoadorable. We brought her home. She was ok for about a month. And then she started to get weird. She slept on the baby gate. On. The. Baby. Gate. She would fall off. Get back up, go to sleep, fall, repeat. All. Night. Long. I really shouldn't speak in past-tense. She still does this. However, for the past few months, she's also taken to sleeping in the kitchen window. But the ledge isn't very wide (it is wider than the baby gate, however). But she still falls off. Into the sink. Which often contains dishes. (It's a House of Sloth, remember). This cat is not right.
I'm thinking it's probably best if I don't have any interactions with Emily's hamster.