The engineers stopped the 'countdown' because something was wrong with the engine.
the 'countdown to' summer vacation
the steady 'countdown to' war
(..) launch pad construction complete? Roger. Rocket is now secured to guide wire. We are currently obtaining the ignition sticks. Countdown will commence momentarily. -Stand by. -Let's go. Hey, Ma! Where are the matches? Oh, wait. Here they are. Never mind. (..)1995 Toy Story