Socialization is an overwhelmingly powerful process, because it goes beyond the individual and whatever personality or character traits they may possess. While parents are the primary agents of socialization, they, too, are products of society and social mores. This is what makes societies distinct from others, but also what makes them pretty consistent over time. Take racism for example, and why it is so slow to improve in a society, because it takes generations to socialize out of the mainstream beliefs being passed on.
Culture is trickier, because there are so many elements to it. Language is constantly changing, and different generations embrace different aspects of culture. They also tend to hold on to that culture for much of their lives, and it is very difficult to change. So we have, essentially, a number of sub-societies that reflect cultural changes from generation to generation.