Not being taken seriously is humiliating. Not in the same way as discovering you're standing in a crowded room wearing only your underpants is humiliating, but humiliating in the sense that you are made to feel like your opinion doesn't matter, you don't know what you're talking about, you're little and your interlocutor is big, and worst of all--there's nothing you can do about it.
Most people do not being the person who's condescended or not taken seriously, and yet we/they continue to condescend and not take seriously people on a regular basis. While some people do know better--your tax man knows whether you can deduct those peep-toe pumps as "work-related attire" or not--they sometimes forget that they are just as fallible as everyone else is. I know a lot about Microsoft Word, but I don't know every little minute detail. I learned something new just a couple weeks ago. I wouldn't say I'm an expert, I'm just quite familiar with it such that I could probably teach the basics to someone new to the program.
Another example: Bank tellers are good at math, theoretically. They count and subtract and crunch numbers on their computers and calculators for people all day. But (we're getting to the crux of the episode, dear readers), mistaking WITHDRAWAL for DEPOSIT as a bank teller is a pretty big difference--perhaps a crucial difference in some cases. You say, for example: I would like to deposit $50 from this check into Account A, and cash the other $50 from the check. They agree, take your account number, and if all goes to plan, subtract that amount from the check and deposit that into the account, giving you the remainder of the check's value back in cash.
Now, when the teller hands you $150 cash back, you may wonder, why am I getting 3 times as much as I asked for? And 50% more than my check was for? The teller must have made a mistake, you think. The teller must have heard withdraw when you said deposit. That's acceptable. People make mistakes. But when you say after this occurs: Excuse me, but I wanted to deposit $50 from my check, not cash it all and withdraw an additional $50 from my account, and the teller still insists they know better--"Oh, that's just the difference between them"--, that's not OK. $100 less in your account may be a pretty dramatic difference for some people.
While the above scenario is a fictionalization of yesterday's excursion to the bank, I think it makes an important point. Make mistakes, learn from them, try not to do them again, but please--pretty please--don't make a mistake and not admit to it. Your mistake is costing me an extra 20 to 30 minutes of my time, and an extra couple bucks of extremely unaffordable gas in my car to come back to the bank to correct the mistake that you refused to correct when I was already there and caught it. It's not like I was belligerent about the error. I simply knew that something had gone awry and wanted to correct it so I would not have to make another trip. Perhaps I should have been more insistent that I shouldn't have had as much cash back as was given, and that might have saved me another trip--but my Tuesdays are rough, and by four in the afternoon, my brain is not in any shape to try to contradict people or argue with them articulately, even if my brain is still functional enough to register that something did go wrong in this particular transaction.
Mistakes are tricky. We don't like to be put down for them, at least not too harshly. But when we make them, most people, or perhaps just people like me, like to know what they are so we can make sure they don't happen again. In any case, when I return to the bank, it'll be to another branch where hopefully the tellers are slightly more competent.
The "Fool me once" proverb does not apply here.