In your life does everything work exactly as it should, all the time?
It certainly does not in my life.
But modern expectations are high.
This includes expectations of coins that are properly conserved, which is another way of saying they are cleaned by professionals.
I had an email from a reader who had submitted some coins to be restored after having been subjected to the ravages of Hurricane Sandy.
Apparently after the work was performed, the reader was not pleased with the results.