GMAT Critical Reasoning (CR) | Re: #Top150 CR: The rise in free, do-it-yourself instructions

C ) The overall sale of online do-it-yourself home repair instructions by home service technicians has not been equal to the loss of revenue the technicians have incurred due to free offerings of this sort of material.

>>Technically, if loss is not equal to sale of online stuff , then some people(if we remove technicians who can take care of themselves and don't cause injuries)is repairing on their own by referring to online repair instructions by some means and causing injuries.