Employees expect to uses their mobile devices at work, and employers often don’t mind because of the cost savings. However, being able to use personal smartphones and other mobile devices at the office creates problems for IT managers. A small business with 100 employees might have an additional 300 “bring your own device” users to contend with, all using phones, tablets and laptops. There are a lot of potential leaks there.
http://robertsiciliano.com/blog/2013/11/23/employees-putting-data-at-risk-on-wifi/