Originally Posted by fastair

5-10 min delay means most likely, arriving 5-10 min later. this means that the aircraft turn will be shorter, increasing the chances that the next flight will not be off the gate on time. Many airports at peak times don't have spare gates, so now, another plane waits for the gate. The concept of "schedule padding" that many on this board seem to think is a waste, and that the crews can just "make up the time in the air", well, clearly it doesn't always work, or we wouldn't have stories like this. The closer to being on schedule flights run, the less the system suffers. A few planes late causes gate changes, sitting in the penalty box, missed connections, lines at the rebook counter.

Airports and flights do not run in a vacuum. Things impact other things. People (crews and passengers) who don't know about the gate plan at an airport can think that holding a few min doesn't hurt anything. Then they wonder why they had to sit waiting for a gate another time missing their connection. This is a network. Just as a highway is. 1 accident on the highway impacts thousands of other drivers for extended periods of time. The Doctor that arrives 30 min late for his 1st appt for the day doesn't just make that one person wait, but that person's appt runs long, making the next person wait....aircraft utilization doesn't have planes sitting around for hours at a time, and gaits sitting open for hours, at least not in the summer time. The margins for errors are there, but they aren't huge, and when summer storms happen almost daily, why would one think that throwing another bad variable into the equation isn't going to have negative consequences?