User Account Control (UAC) is one of Microsofts new methods for attempting to protect users who are always logged on as an administrator. Microsoft has been telling administrators and end-users not to be logged on elevated all the time for many years. By default, UAC does not apply to the built-in Administrator (RID 500) Windows creates two log-on sessions: one elevated, one not elevated. UAC (again, in most cases) does not detect whether or not a program needs to be elevated.”]
Source: https://www.csoonline.com/article/2633176/user-access-control-in-a-nutshell.html