It seems that many of the groomers do the grooming in stages. All dogs washed, all dogs nails, all dogs hair cut etc so that it takes a whole day to do the grooming. I think that it stresses out many dogs to spend the whole day and the groomer that we originally used did not take them out for a pee break.
I have since found a new groomer that does each dog start to finish. Punkin is done in an hour and a half or less
She also grooms in a store front window so you know that the dogs are being treated very well.