I was kept waiting 27 minutes only to be told my appt. was too soon. Obviously your email doesn't work well enough to tell your patient that the appt. should be rescheduled, you just want to confirm the appt. by email which I did.
Also, I can understand being kept waiting by the Dr. for an emergency, but being kept waiting for a cleaning has not happened to me in 30 years!
I am your hygienist and I am here for you. But remember, I am also here for the person before you. If I am running later than scheduled appointment time, I sincerely apologize. The patient before you made have had an extra question or just needed my comfort. Please understand that one day YOU may need that extra attention.