Sometimes it is the case that there is too much pride involved with checking the work. At one point we had a subcontractor helping with installations. He thought that he was so good that he didn't need to check anything. He'd be out in the field and call in "not working" -- indicating that this was a design issue and he would leave. Worse, he would tell the customer "done" and leave. A few minutes later the customer would call with a "not working" complaint. In both cases we would go out and have the system working in a minute or two. (these were complicated issues, such as plugging in an IR emitter) Needless to say, we don't use that sub anymore.