There are a plethora of theories that purport to address why people commit crime in general.   The theories briefly discussed below are those theories that address causes in crime, in general, but also seem a particularly good explanation for cyber crime in particular

Rational Choice Theory

People make a calculated, rational choice to commit crime.  The potential criminal weighs the risks and the benefits.  If the benefits outweigh the risks, crime is likely to occur.  Risks and benefits can be both tangible and intangible.  For example, money is a tangible benefit while prestige is an intangible benefit.  Yet, both motivate behavior.

Routine Activities Theory

There needs to be three factors in order for crime to occur:

If any of these things are missing, crime is unlikely to occur.

Subcultural Theory

A sub-culture is a social group with shared characteristics that distinguish it in some way from the dominant cultural group.  Such groups hold norms, values and beliefs that are in opposition to the larger culture.  People behave consistently with the norms and values of their subculture – even a criminal subculture.  Criminal sub- cultures, for example, gain prestige from committing crime and ‘brag’ about it.  Conversely, members of the mainstream group would be shamed.  

This theory explains ‘hacking’ particularly well as hackers have a very specific subculture

Anonymity

Anonymity is a condition in which one's true identity is unknown.  It is the quality of being unknown or unacknowledged.  People are more likely to commit crime if they can remain anonymous.  Being anonymous makes it less likely that the perpetrator committing the crime will be caught.  Consistent with this, environments in which perpetrators can remain anonymous are typically those which will experience more crime. It is quite easy to remain anonymous in cyber space which suggests it is an environment at risk for criminal activity