The initial intent of this combination was to use for system reboot. This was made know by Bill Gates at an interview session at Harvard. He said this mistake was from the end of the IBM keyboard designer, David Bradley.
Gates also said, “So we could have had a single button, but the guy who did the IBM keyboard design didn’t want to give us our single button.”
Even though the three-key combination as been seen a mistake, it still part of the new generation Windows system, Windows 8.
Bill Gates also admitted some other mistakes like their latest in the mobile market. They couldn’t nail the mobile market when they had opportunity to.