In The Hydraulic Troubleshooting Handbook I define and explain 12 principles for troubleshooting anything successfully. And I use examples from various fields of endeavor, in addition to hydraulics, including medicine and IT.
Troubleshooting Principle #5 is: Never Take Anyone Else's Word For It. And I observed a good example of the application of this principle recently when, after moving from one side of the country to the other, I was having trouble with my broadband connection.
I was on the telephone to a technician in my ISP's support department. Keep in mind these guys are professional troubleshooters--by remote. The technician wanted to check my modem's settings, so he guided me through the necessary steps until we reached a point where a password was required for access. Apparently, by default from the factory, the password is either blank (no password) or 'admin'--unless someone changes it, which I don't remember doing. So he asked me to try 'admin' first. I keyed in: a-d-m-i-n and hit enter. The result: "incorrect password". Next he asked me to leave the password field blank, which I did and hit enter. Same result: "incorrect password".
Having come to a dead end, the technician politely asked if I would allow him to have remote access to my computer, which I agreed to. This took a few minutes to set up. As soon as the technician had remote control of my keyboard and mouse, the first thing he did was try the two, default password options for himself. In other words, the main reason he wanted remote access to my computer was because he wasn't willing to believe I'd followed his instructions correctly.
What he'd asked me to do was not at all difficult, and I'd done exactly as he'd asked. But when you think about it, these guys must come across the opposite all the time. After all, they're attempting to troubleshoot remotely through an 'avatar' of unknown capability and computer literacy. And as such, they must always be skeptical that what their 'avatar' is doing and telling them is accurate!
To relate this to a hydraulic troubleshooting situation, it means if someone tells you the hydraulic tank has got plenty of oil in it, or the system doesn't have a suction strainer, or the direction of pump rotation is correct, you should, like the technician in the above story did, thank them for the information and go check it for yourself.
We're conditioned to believe what we're told. Especially when we've no reason to doubt the intentions of whoever is telling the story. But to be most effective in a troubleshooting situation, this natural willingness to believe must be replaced with vigorous skepticism. Failure to adopt this approach can lead to the wrong conclusions and prolong the troubleshooting effort--both of which can be costly. And to discover six other costly mistakes you want to be sure to avoid with your hydraulic equipment, get "Six Costly Mistakes Most Hydraulics Users Make... And How You Can Avoid Them!" available for FREE download here.