An airplane’s in-flight entertainment recently offered me a choice of shows to watch. I picked NBC’s “Great News” — an episode I’d seen before. I watched and laughed. Ten minutes after it ended, I was feeling bored. So I watched it again. And I still laughed.

This experience made me feel stupid. How could I watch the same show over and over?

Then I did some research and discovered a little-known fact: The world of TV watchers is made up of repeaters and one-timers.

One-timers watch an episode and have no desire to watch it again. Then there are the rest of us. If you like an episode, why not enjoy it one more time? Or two. Or three.

Not every show is worthy of re-watching. The suspense of a drama can fall flat the second time around. I don’t do “How to Get Away With Murder” reruns because I already know who got away with murder.

But sitcoms are great fodder for repeaters. I polled friends and family, who confessed to repeat-watching shows such as “Seinfeld,” “Broad City” and “How I Met Your Mother.” They said the shows are so dense with jokes that there’s no way you can catch them all on the first viewing.

And if a joke made you laugh once, it’ll make you laugh once more. When Jerry makes Elaine chortle by standing a Pez dispenser on her leg during a piano concert, I chortle along with her.

In a way, we repeaters are reliving our childhood. Kids will watch the same episode of “Sesame Street” or “SpongeBob SquarePants” ad infinitum.

There’s something comforting about the familiarity of it all. And it is nice to know what will happen next!

But even diehard repeaters have their limits — typically three viewings of a single episode, based on my unscientific research. Although one repeater said he could watch a single episode of “Golden Girls” up to 12 times.

A footnote: Repeaters aren’t clueless. We recognize we might have a problem. Said one repeat viewer of her endless viewing of “Real Housewives” episodes: “I can say all their lines with them. IT IS A SAD THING.”

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