Ask yourself this: "Of all the networking events I've been to, how many of those people have I followed up with a phone call, email or other contact?"  

I know the answer. Almost none.  I can say that with certainty because in over two years I've only had four people ever follow up with me.

This seems to be a major problem. 

A local business man who needed some work done complained that he called a number of vendors to come out and give him a quote.  Yet, he said a lot of them didn't even return the call and some who said they would come didn't bother to show up.

The simplest and cheapest thing you can do to build future business is to follow up after an event and make contact.  Sure it may take time. But, why throw away warm prospects again and again then wonder why business is down? 

Follow up! I and others like me are still waiting to hear from you.