Having the AccessibleDescription property set appropriately for controls is one of the requirements for applications that support Windows Accessibility standards. Windows Accessibility standards are designed to help people with disabilities use applications more effectively. Many businesses, governments agencies, and educational organizations have accessibility regulations, and an application must meet accessibility requirements to be considered certified for Windows.
' VB
[ControlName].AccessibleDescription = "A form for editing employee information."
// C#
[ControlName].AccessibleDescription = "A form for editing employee information.";