Has this ever happened to you?
There are problems with the installation. Numerous phone calls have been made. Remote trouble shooting hasn’t helped. You were assured that everything was properly installed and in order. You send someone out to the location, or maybe you even went there yourself. What did you find? Loose wires. Unmarked wires. Un-grounded shielding. Poor terminations. It’s a mess. And, it’s the reason for the failure.