"Poor socialization" refers to a lack of or ineffective development of social skills. It means that an individual may struggle to interact and communicate with others in a productive and comfortable way. Full definition
Many dogs arrive with poor socialization skills requiring months of handling with humans and other dogs. (dobiesos.net)
Puppies that are taken away from their moms and siblings too soon can develop poor socialization skills. (hartz.com)
A dog who doesn't interact well with other dogs or people isn't typically the fault of any disorder; it's a product of poor socialization as a puppy. (smartdogowners.com)