Puppies are getting used to sleeping in a crate (open door) to get them used to eventual crate-training.
Appropriate socialization is critical to a puppy's development. These puppies live in the breakfast nook at one end of our family kitchen. While they have their own private space, they are still exposed to the noise and bustle of normal life. They get very excited when the family goes into their enclosure for gentle play.
At the puppies' impressionable young age, we want all of their experiences to be positive. All interactions with people are carefully monitored and controlled so that they leave nothing but good associations.