While attending US Army's Airborne School.....

The Day before our first jump, the instructors (known as SGT Airbornes, students are called 'Airborne') demonstrated all the possible malfunctions one might encounter. 

After watching a total malfunction, i.e.  the parachute fails to deploy, one of the students asked: "SGT Airborne, if we have a complete malfunction, how much time do we have to deploy our reserve parachutes?"

"Airborne, you have the REST of your life to deploy that reserve!"