The criminality of an individual is by itself not sufficient for a crime to occur. Though in many cases, a criminal will be so determined to commit a crime that it will be impossible to deter, the circumstances of the situation and environment need to have certain characteristics for a crime to be possible.
Situational Crime Prevention works on four principles: that if the effort needed by the criminal to commit the crime is increased, that if the risks to the criminal during perpetration are increased, if the potential rewards for the crime are reduced, and if the excuses to plead ignorance of the act being illegal are removed, then the likelihood of the crime being committed drops significantly.
In many environments it is impossible to remove the assets on site that make tempting targets for an intrusion. That leaves the best path to stopping one to be making it clear to the potential intruder that his goals in theft or vandalism will be extremely difficult to achieve, and impossible to do so without being identified. With hardening measures such as physical barriers and access control systems, and highly visible surveillance by cameras, or most effectively by live personnel that can react to an situation immediately, almost any area will be passed on for a more vulnerable and less intimidating target.