Not fair to assume OP is a frequent flyer, and even less fair to give him a hard time or be dismissive about the reaction.

To be honest, this (delay, delay, delay, cancellation) does happen frequently on any airline. Happened to me on AA, US, and UA in the past year, and one of those was ORD-LHR! It's too bad, particularly when it disrupts your personal/business plans, but such is life and you have learn to roll with it. You can't blame the crew, so no use yelling at them. Same with the gate agents. They don't control whether or not the flight is allowed to take off.