It seems the reason they thought they were done counting is because a supervisor told the counters to go home, and said that they were done counting for the day.
Relevant part from the linked document (paragraph 8):
"Sometime after 10 o'clock p.m., the counting activity slowed. Shortly afterward, a younger lady with long braided but blond hair yelled out to all of them they should stop working and come back tomorrow (the next day, Wednesday November 4th) at 8:30 A.M.. Thereafter, all but 4 election employees left State Farm, leaving just the blond haired lady (who Michelle and I assumed was the supervisor), two older ladies and Regina Waller at the location. This lady had appeared through the night and Michelle and I believed her to be the supervisor."
I think that while it is possible the observers could have just stayed there until everyone left, it is likely that they believed what they were told -- that the counting would finish the next day.
At any rate, it is at best a bad look. I agree that it doesn't prove fraud or anything close. It does, however, look suspicious and IMHO warrants further investigation.
What the state investigator says, and what those affidavits both appear to agree with, is
> Nobody told them to stay. Nobody told them to leave. Nobody gave them any advice on what they should do. And It was still open for them or the public to come back in to view at whatever time they wanted to, as long as they were still working.
I’m going to give more credence to the affidavits of the people who were directly involved over the wording from ABC.
One of them did return later and was allowed in, but arrived as the counting was complete.
It’s an unfortunate situation that everyone was told it was closing down and then the secretary of state’s office called to tell them to keep counting, but that doesn’t support Giuliano’s claims about rigging the election with suitcases of ballots from under a table.