Miscellaneous errors, such as a staffer sending private information to the wrong email address, is the leading cause of data breaches, according to a new report from Verizon. These mistakes accounted for 29.4 percent of data breaches in 2014, up from 25 percent in 2013 according to Verizon's annual Data Breach Investigations Report. While at times computer error is at fault, 60 percent of the time, user's make a mistake.