Honestly, one of them was like that from the day they got her. When they first got her we were all kind of concerned that even as a puppy she was always just kind of sitting and watching, never really played or interacted that much. The other I don't know well enough, but she is constantly with her owner, travels, eats well, doesn't live in a cage, has a huge comfortable home, is the dominate dog in that house as well, and is treated mostly like a princess. But doesn't play, mostly just lays around, doesn't attempt to do anything and just blankly stares.
The other though, from day one was that way, we think she might have some brain issues, she isn't smart at all. And lives with another dog that is totally fine. She came from a puppy mill style place as well, so we wondered if it was breeding as she has had a TON of health issues as well. Not all dogs like that are abused or neglected, and this one definitely isn't neglected her owner treats her like the world, some dogs are like people just not the brightest of the bunch.
And in this family I'd pay to be these owner's dogs. Never seen one hit by their owner, they want for nothing, and are in their presence constantly. Rarely left anywhere and if they are left, left with family they know. To clarify, indoor, lap dogs (Bichon Frise, and Toy/teacup Pom)