Windows intentionally delays startup applications by 10 seconds after login to let the desktop and shell finish loading first. While well-intentioned, this delay means your tray apps, password manager, and other tools you rely on aren’t ready for nearly a quarter of a minute after you log in.
This registry tweak sets the startup delay to 0 milliseconds. Startup apps will launch as soon as Explorer is ready, without the artificial wait.
The Serialize key may not exist by default, so the command creates it first if needed, then sets the value. The change applies on your next login.