I'd like to say it's fun having an adoption center where I work, but the reality is I see a massive amount of puppies returned to the shelter for basic things like potty training issues, barking, chewing, and pulling on the leash. One woman returned a puppy that she said kept biting her child. It was biting because her child kept hitting it in the face and she thought the puppy should just be fine with that.
As much as I want the dogs and cats to find a home, I have to admit, I've openly discouraged some people that made it obvious they were making an impulse decision.
One woman wanted an 8 week old black lab puppy, then proceeded to ask me how she could take care of it in a way where she would never have to take it on walks, it wouldn't shed any hair on her pure white carpet and couches, it would never touch any of her things, and she would never have to deal with any potty accidents. I told her to leave and get a pet rock. I hear granite has quite the personality.