Security is now technical. Long ago it may have been OK to hire a security wannabe who had taken a class or learned on the job. Today the job requires experienced engineers who have a proven history of understanding and designing hardware, software and human interfaces.
Being able to recognize security threats in unfamiliar (or concealed) hardware can only come from an understanding of technology basics. Our background of engineering design work with mechanical, electronic, software and user interfaces is very helpful when investigating complex forensic cases.
Investigations in the executive suite need particular attention to detail. We expect that eavesdropping devices will be concealed and may be just a small modification of existing devices. When something odd is discovered, just identifying it is not enough. We need to understand its context, significance and threat level.
In a major US company we took this process a step further. When a new headquarters building was designed we worked with the architect to harden the executive suite against physical attacks and electronic eavesdropping. This involved knowing security practices but mostly relied on the experience of engineers on our staff to provide new solutions to increase electronic security.
A walk-through after the walls are up is too late to make much of a difference in security.