A paper list and handwriting
The scope is settled in conversation
Which display case or which category was counted changes from person to person.
Pieces are written down one by one
Hundreds of pieces are read and ticked by hand, and a piece that is skipped does not show up as a difference.
The result stays on paper
It cannot be compared with the previous count and the record cannot be shared.
The count is done, but where the difference is nobody knows.