When you hibernate, Windows saves the entire system state, including all your open programs and files, to disk so you can quickly resume from where you left off.įast Startup mixes the traditional shutdown process with hibernation. In the traditional shutdown process, Windows fully shuts down everything, discards the running system state, and starts up from scratch the next time the PC boots. RELATED: The Pros and Cons of Windows 10's 'Fast Startup' Mode This feature was introduced in Windows 8, and has also been called Fast Boot and Hybrid Boot or Hybrid Shutdown. This weirdness is all thanks to Windows 10’s “Fast Startup” feature, which is enabled by default. Why Doesn’t the “Shut Down” Option Fully Shut Down?