A child that is left alone the whole day will be prone to be less communicative. Babies pick up sounds and voices around them. So, a child that has more people around him/her will be able to communicate better and faster. Such a child would have an advantage and be able to adjust better to surroundings and society.
Good communication skills are of prime importance, whether at institutional level or at the home-front. A child that is used to conversation with the parents at home in the early years will be able to interact better in the school/college. A child that is not used to people around him/her might tend to be an introvert and might even become less sociable in the long run.
Situations that discourage adequate early language development might be numerous. The most important among these could be shyness due to low interaction with parents/peers and others in the early years. When both the parents are working or busy otherwise, and do not interact with the child much, it might adversely affect the language development. Other factors could be medical conditions like stammering of speech, hearing impairment, and other disabilities.
Constant rebuttal by parents /teachers/peers is another factor that could discourage adequate early language development.