User Account Control will appear about one-third less often in Windows 7 than in Vista. The feature is designed to reduce the chance that malware could hijack a PC. The move to scale back UAC prompts came after an internal study found that users were suffering from “click fatigue” Microsoft Corp.’s director of Windows 7 client enterprise security says the feature will drop 29% in the new version of the operating system. The UAC feature is intended to prevent malware hijacking a PC by forcing users to confirm that they really intend to do things such as install software.”]
Source: https://www.csoonline.com/article/2123971/microsoft-cuts-uac-prompts-in-windows-7.html