A glitch disabled registers at thousands of Starbucks stores on Friday. All company-owned stores were affected by this outage, about 60% of its 13,500 locations in the U.S. and Canada. As with many point-of-sale systems, Starbucks’ registers collect data, run their loyalty program, and process credit cards.Failure of this one technology represents a killing blow that small and medium businesses need to know how to avoid. For more information on this topic click here.