All of these quotes combined, and in no particular order, are as practical as they are motivational. Although they should be self-explanatory, we'll break down what they mean below.
You should start your network early, much earlier than you need to. If you want to be an MBA student, you should start networking before. If you plan to work at a specific company, don't wait to join the company to start networking. Who knows, maybe those connections can expedite things.
Networking gets such a negative connotation as being a "fake" or "selfish" act to get something from another person. However, it is important to remember that network is about relationship building. This quote by Ivan Misner is a reminder that Networking is more about cultivating great relationships with people rather than just being transactional.
Similar to the first quote, networking can help expedite things for you. If you want to work at Google, reaching out to people that work at Google can help give you insight as well as a possible referral into the company. Similarly, having someone in your network that has specific experiences means that you can leverage their knowledge and experience in that area as if they are your own.
Networking is not just about gain but also about giving. Networking is not a zero sum game where one person has to lose something for the other to gain, it is a two way street. If you give more than you try to gain then people will reciprocate and be more willing to help you whenever you need it. If you only take then your network becomes harder to leverage.
What Harvey means here is to never expect anything in return. You should try to be more generous than the other person and give as much as you can without expecting anything in return. If you do this then when the time comes you'll have the confidence to ask for favors without feeling guilty. As Keith said, the currency of real networking is not greed by generosity.
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