I've been very fortunate in my life. Can't recall EVER having a flight I was on cancelled. Rarely delayed.
SF is currently down to one runway for landings due to construction. Our departure from Denver was supposed to be at 11:30, MDT... and if you want me to prove this next part I can send you the alerts I got from Tripit, and Orbitz, while in Denver.
Soon as we landed they announced an hour delay. The next came in what seemed like 20 minute intervals:
Delay.. now 12:30...
Delay.. Now 1:30... with a new gate and new seats.
Delay... Now 2:30 with a new gate and new seats.
Delay..Now 3:30 with a new gate and seats.
BUMP UP... never heard of this one... back to 2:30.
Delay... back to 3:30
Delay, now 4:30 with a new gate and seats
Delay, now 5:30
Bump UP.. back to 4:30
Delay... Now 4:46. They started boarding then made an announcement... they were halting boarding because SF hadn't given them a clearance to takeoff. (good thing, better to lounge at the gate than in a seat)
Delay... Now 5:15.
We left about 5. - JamesJM