I was at the grocery store for the weekly supply run, checking out. The cashier was a personable young woman, probably a college student, and she greeted me brightly. When I held up my phone to display my loyalty-card bar code, she apologized and said her handheld scanner was out of order. No worries, I said, and gave her my phone number instead.

She began unloading my cart, passing the items one by one over the stationary scanner. Meanwhile I stuck my debit card in the PIN pad and punched buttons, not really paying attention to what she was doing. Then I looked up and saw that this young lady was wrestling the 35-pack of bottled water out from under my cart and maneuvering it across the scanner. I had completely forgotten that it was there, and it hadn’t occurred to me that with her handheld scanner broken, she’d have to do this. By the time I noticed, however, it was too late for me to help.

I laughed awkwardly and said “I guess sometimes a broken scanner is really inconvenient.” Apparently I must have decided that my attempt at humor wasn’t sufficiently lame, because I added “Lift with your legs, not your back!” I meant it as a humorous acknowledgement of how hard her job was, but I knew as soon as I said it that it didn’t work. Here I was, standing there watching her do all the work, making no move to help, and joking about it. I just hoped it didn’t come across that way.

She finished ringing me up, and I thanked her as I began to wheel the loaded cart away. She looked me straight in the eye, a smile frozen on her face, and said “Have an absolutely wonderful day!”

OK. Maybe she really meant it. Maybe she’s just one of those sunny people who talks like that. But I have a suspicion that she was actually making an effort to be the courteous employee, putting on an over-the-top performance while on the inside she was thinking “What a jerk.”

As I walked out to the car I felt embarrassed for having given her the wrong impression. I know myself: I know that I am a kind, caring, sensitive guy. I’m one of the good ones. How sad that I had accidentally left this cashier with the wrong impression about me.

But then a disturbing thought occurred to me: maybe … she’s right. Maybe I am a jerk.

People judge us by our actions and words, not by the thoughts we keep to ourselves. It doesn’t matter what we’re thinking when we’re rude. That’s why social niceties require attention and work, because they don’t happen automatically just because you mean well.

Unfortunately, as I’ve gotten older, I’ve become busier and more distracted. I tend to be absorbed in my own thoughts a lot of the time, and I always feel like I’m in a hurry. Added to that is my natural shyness, which has always made me awkward in social situations. So I’m more likely to distract myself with my smartphone than to engage in casual smalltalk; I keep my head down when I’m walking; I breeze past people rather than say hello. And if I find myself forced to interact with someone I don’t know well, I fall back on lame humor, because I don’t know how to do anything else.

It doesn’t matter if I’m a kind person on the inside. On the outside, I’m afraid I am sometimes a jerk. Not because I intend to be; not because I bear ill will toward anyone; but because it’s hard work to be nice to people, and I haven’t made it a habit to try hard enough. This is a sobering realization, and I think it’s something I have to do better at.

But I suspect the next time I go to that grocery store, if I see that cashier working again, I’ll probably just go to a different register. Maybe to the self-checkout line, where I won’t have to interact with anyone at all. It’s easier that way.