Most of the parents fail at parenting because they don't know about their primary job as a parent. This is the basic component of this job so knowing it in detail is very important for you and the future of your child.
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"Your primary job as a parent is to prepare your child for how the world really works. In the real world, you don't always get what you want." - Dr. Phil
When we start parenting our children without defining the main purpose/goal, we do it in the wrong way. The result is a grown up who is not prepared to accept responsibilities of his life. Hence becomes dysfunctional member of the society.
74% of the parents say they provide financial support to their 18 to 29 years old children. - Clark University Poll of Parents of Emerging Adults
Press Release: Clark University - Wed, June 26, 2013.
So, whatever you want your children to become, now is the time to take the right steps keeping in view the ultimate goal of parenting that is preparing your children to perform good in the real world. There should not any disconnect between your parenting and the real world situations.
Finally, here is something Julie Lythcott-Haims has to say on over-parenting:
If you're a parent, describe your experience in the comments.