A: The simple answer is - to save money. The amountof money spent by consumers at shops that "throwparts" at problems in hopes of hitting the lucky fix is staggering. Testing performed by technicians with the proper equipment, training, and technical resources allows your repair to be targeted at the cause instead of trying expensive guesses. Such testing may seem costly at first, but it is actually much more cost effective than guessing at the correct fix. Would you prefer to pay $200 in testing and $200 in repairs, or free testing and $800 in repairs?