[QUOTE=rickair7777;515685]
Look at recent history...I can't recall any solid fuel booster failures in the last two decades, but there have been numerous, recent, major malfunctions of liquid engines.

Even the shuttle Challenger booster did not fail...it leaked, but it continued to function normally. The leak ignited the liquid fuel tank.
QUOTE]

I'd call that a failure. A leak that leads to a failure is a failure. The problem may not have been the propellant, but it was still a failure. The dead astronauts would also call it a failure.