“Thank you for your patience” has become one of those expressions that makes me cringe whenever I hear it.
The idea itself is not bad. The problem is that it’s invariably used to refer to situations in which the “patient” person didn’t have a choice about being patient. Like, when the Metro operator says “thank you for your patience” while pulling the train into the tunnel after being stuck at the platform for 20 minutes, that doesn’t really make sense. We weren’t being “patient” by sitting nicely in the train cars while going nowhere. We were taking what was given to us. The alternative would be to get out and walk, which tends to be a net loss in terms of getting to work on time.
The question is: “If I were not patient, would you do anything differently?”
If the answer is “no,” then “patience” is a meaningless concept. If you’re not going to move any faster regardless of someone else’s ability to stay calm while they wait, then there’s no meaningful communication in saying thank you for their patience. The sentence boils down to, “Well, look at that, you’ve been caused some inconvenience.” I’m aware that we Americans tend to say “thank you” compulsively, but we could still stand to be honest about what the phrase actually means.