I'd write. Remember: The doctor is your "employees". You hire them to do a GOOD job...and if they do not meet expectations (ie: LONG waiting hours) then tell them in a courteous way, of course. It's way too uncomfortable for your mother...and you! What if you'd had other appointments etc?

Sounds like she overbooks herself...which could mean she's overworked...which could mean her attention to details could be lacking...which could mean patients suffer in the long run.
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