I like how one of my flights arrived in YYZ, deplaned, got groomed, got crewed and then boarding was delayed because the jet bridge "wasn't working". They blamed the GTAA (of course) but what the heck did they do between the crew going on and us boarding? Cost us an extra 20 minutes delay.

For me, it's all the little 15 or 20 minute delays on the ground that add up to make >50% of my flights late.