As a Chihuahua owner, I must disagree with OP's statement.
My Chihuahua is 11 years old in human years (77 in dog years). If we put him in his cage at night, he will bark for three hours until we let him out. This is at 12 o'clock at night. We can take him out for 5 minutes or 5 hours, and he will always come inside and pee on a chair/poop on my mom's bedroom floor. He will scratch at the placemat in his cage regardless of whether or not he has food, and he literally yawns at the food you give him when he first gets it, regardless of how big of a fit he threw before you gave it to him. He hates anyone who isn't my mom (including me, even though I've lived with him since we got him and have taken care of him a lot more than she has) and constantly pees on my floor without me noticing, which is why my room tends to smell bad every few months. He has vomited on every blanket and pillow I've owned, and the stains of that have yet to come out. I've step in more of his droppings that he's actually dropped. He humped my step-grandma's arm about three times before anyone stopped him. He drips water on the floor that I step on. He has one tooth and I have to crunch up his solid dog food before he can eat it. I also have to mash up his soft dog food with a fork before I give it to him because his esophagus is so small that he can't actually swallow large food and he can't chew it up because he has one tooth. He also smells nasty and his farts have probably given me radiation poisoning.
Chihuahuas are NOT adorable. They are the spawn of Satan.