Why did Anwar Sadat start Yom Kuppur War against Israel right on Kibbutz Day in 1973, catching Israel napping?

He knew from intelligence sources that Israel was preparing for the war. He declared that weeks before Israel would have started as a pre-empted move incurring heavy losses of Israel. It was ended after the statement of Sadat that he was well set to use surface to surface ZAFAR missile to hit Tel Aviv directly. War immediately ended after that b coz Israel thought that might have a nuclear warhead which was not the case & ISREAL WAS FOOLED SO EASILY. Even afterwards, during negotiations, Henry Kissinger of USA, tried to entrap Sadat on Israel's behalf for solid peace process in return of big concessions from Egypt through FRAUD TRICKS, but, Sadat, reading minds of Isrealis & USA's lobbies accurately, could not be fudged like Shaikh Abdullah of Kashmir( in 1947 by Nehru, the then prime minister of India).