What makes an expert Troubleshooter?

One trait of expert troubleshooters is that they are able to find virtually any fault in a reasonable amount of time. Easy faults, complicated faults, they find them all. Another trait is that they typically replace only the components that are defective. They seem to have a knack for finding out exactly what is wrong. No trial and error here. So what is their secret?

You might think that a person who has a very good understanding of how the equipment works, should be able to troubleshoot it effectively. Being a good at troubleshooting requires more than this.

Expert troubleshooters have a good understanding of the operation of electrical components that are used in circuits they are familiar with, and even ones they are not. They use a system or approach that allows them to logically and systematically analyze a circuit and determine exactly what is wrong. They also understand and effectively use tools such as prints, diagrams and test instruments to identify defective components. Finally, they have had the opportunity to develop and refine their troubleshooting skills.