Large amounts of money can be offered to perform a specific task in a business environment. This could be installing a Remote Access Trojan on the business network.
Humans can be forced to do things they do not want to do. Like the saying goes; EVERYONE has a price. Remember that the price does not explicitly has to be money. For example; unwanted pictures are often used to black mail victims.
Humans, we, will make mistakes! Hackers and cybercriminals are aware of these types of mistakes and they will try to create environment which increase the chance of such type of mistakes. A simple example is the infection of the CEO laptop, the CEO laptop could be infected by “accident”, the child of the CEO was playing on the laptop and accidently downloaded a remote access trojan.