Anything can happen that can delay the start of the next dog. Some handlers are really good and will have their dog on the start line when the judge told them to, but I've seen some who are distracted or still warming up their dog.
There are plenty of other reasons for delays. The one's I've seen are: not enough volunteers for the ring to start, timer stopped working, fixing knocked jumps and chute, changing jump heights, a dog in the ring gets the zoomies, dog in the ring goes over sct, judge needs a second to breathe, etc. You also have to assume that there are going to be scratched dogs or dogs who moved into your class.
I haven't been to as many trials as most forum members, but I have never been to one that has ran early or even on time. The majority of them are 30-45 mins behind schedule. The worst one I went to was over 2 hours behind. I may be exaggerating a little, but I feel like it was close to 3 hours.
I always try to show up an hour before my schedule walk. Tomorrow I'm entered in the first class of the day, so I'll show up 30 mins before. Just enough time to set up my tent and check in. And then my next run isn't for 4-5 hours. Maybe I can take a nap.
Vey true Randi.The only trials I have ever seen go overtime is NADAC and USDAA if it is a one ring trial.I have never seen a person not have their dog on the line when told but there is always a first.

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