One of the benefits to MDMs is that they restrict access to certain files on a device. Enterprise data, or information that could cause a company or government harm if it was not safeguarded, is often controlled by using applications that are specifically written for an MDM or are wrapped by an MDM to eliminate unintended accesses.
After reviewing multiple MDMs, they each seem to take a different approach to protecting data. Some will encrypt the entire contents of a partition (similar to BlackBerry devices in Workspace only mode). Other MDMs may restrict certain applications only, like those that are used in the course of business, for example, company email, word processing applications, accounting applications, etc.
While most MDMs do provide sufficient protections and prohibit the access of certain applications, not all of them function without faults. Upon testing some popular solutions, many applications were still providing user-generated data unencrypted in areas of the device.