Investigation and diagnosis is an iterative phase - it is repeated several times, each time getting closer to the intended
result. During this process more expertise might be needed, i.e. specialists of a support group may assist with the analysis
and diagnosis of the Problem.
Problems are not only caused by hardware and software. They can be caused by a documentation error, human or procedural error,
such as releasing the wrong software version.
Most Errors can be traced to infrastructure components.