According to the FBI Bank Crime​ Statistics, there were more than​ 4,000 bank robberies in the United States in​ 2015, an increase of 3.9 percent over 2014. The FBI claims that banks have made themselves easy targets by refusing to install clear acrylic​ partitions, called bandit barriers​, that separate bank tellers from the public. According to a special agent with the​ FBI, ​"Bandit barriers are a great deterrent.​ We've talked to guys who rob​ banks, and as soon as they see a bandit​ barrier, they go find another​ bank." ​Sources: U.S. Department of​ Justice, Federal Bureau of​ Investigation, "Bank Crime Statistics​ 2015," and​ "Bank Crime Statistics ​2014"​; and Richard​ Cowen, "FBI: Banks Are to Blame for Rise in​ Robberies," NorthJersey​, March​ 10, 2009. Despite this​ finding, many banks have been reluctant to install these barriers.​ Wouldn't banks have a strong incentive to install bandit barriers to deter​ robberies? Why,​ then, do so many banks not do​ so?