"I wonder sometimes if manufacturers of foolproof items keep a fool or two on their payroll to test things"

In this quote, Alan Coren is questioning the reliability of so-called "sure-fire" products. He questions if the makers of these items actually use someone who is not very intelligent to check them out. This recommends that despite the fact that these products are marketed as being sure-fire, there might still be flaws or mistakes that only a fool would make. Coren's declaration likewise suggests that these producers might not have total faith in their own products, and need to have a fool test them to guarantee their efficiency. In general, this quote highlights the idea that even the most apparently best things may not be as sure-fire as they claim to be.