There are several reasons why parenting experts argue that an excessively authoritarian parenting style can be ineffective. Obviously, some authority is necessary in that one would not wish to let kids learn by experience that electrical outlets and hot stoves are dangerous, and so it makes sense to have strict rules about matters where children might cause immediate danger to themselves or others. Where immediate safety issues are not at stake, though, there are several negative aspects to authoritarian parenting.
Perhaps the worst aspect of authoritarian parenting is that it does not prepare children to think for themselves, and thus is not a good preparation for adulthood. On a social and political level, people used to unthinking obedience to authority easily fall prey to demagogues and dictatorial leaders who thrive because of a habit of unquestioning obedience. The Milgram experiments show the horrific consequences of people trained to blind obedience.
The next problem with authoritarian parenting is that it is correlated with low self esteem in children and lack of emotional and social skills. Children with authoritarian parents, according to certain studies are prone to "depression, delinquency, and alcohol problems".
In today's entrepreneurial environment, much of career success depends on ability to innovate and work independently rather than just being a cog in a corporate structure. This means that children brought up in an authoritarian environment would be at a career disadvantage.
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