I spent about 20 years of my career working in IBM’s midrange computer market with the AS/400 which today is an operating system called IBM i that runs on IBM Power Systems hardware. I moved into the AS/400 world from managing IBM mainframe computers. In the mainframe world IBM published extensive documentation that told you precisely how the system worked.
In the midrange market and AS/400 world there was no documentation. IT people I worked with would tell me how they “thought” something work and many treated their “theories” as truth. Much of what they told me didn’t make sense. I got involved with various user groups and got to know a number of IBM folks in the development labs. I also called IBM support and asked questions and got referred to people who could give me definitive answers.
Today a huge population of IT people just “assume” they know what they are doing or are talking about and do not. This is often the cause of security exposures resulting in compromise and loss of critical data, system failures, failed system projects, and many other problems.
This is one more reason I recommend doing an objective assessment of your computer systems and your IT staff.