The unfortunate bottom line of networking security problems is that hacking happens because it is allowed to happen. Most cases of fraud could have been prevented if people had just adhered to sensible protocols and properly implemented available security solutions. It cannot be stressed enough that the big problem with IT security is people - you, me, and the vast majority of people in the world who interface with IT systems.
It is far easier to get vital information from a person than it is to extract it from a well organized and protected computer system. That's seems like a fantastic statement, but it is absolutely true. If a complete security architecture is deployed, maintained and followed, then it is very difficult to penetrate systems. But humans are another problem entirely.
Social Engineering: The Biggest Risk to Internet Security