If you've ever run into Target to pick up a few necessities and walked out with a cart full of random tchotchkes, you've experienced this retail phenomenon.

Target Storefront
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It's a familiar scene: you swing by Target to pick up one or two necessities and walk out with a bright red cart full of random tchotchkes. A novelty travel mug, a set bath towels and a trendy new purse? Why, yes please!

It happens to all of us, and with such frequency that the "Target effect" has become a bit of a running joke. (It even has its own Urban Dictionary entry!) But it's also a noted phenomenon, and there are plenty of respected experts who are willing to vouch for its existence. As Dr. Kevin Chapman, a Kentucky-based psychologist and admitted fan of the red-and-white bullseye, recently explained to Refinery29, not only is the "Target effect" real, it's no accident either.

According to Chapman, one reason why Target is particularly adept at enticing unplanned spending is that the company has a long history of working with some of the best design minds. These people help ensure that the store's in-house products are a cut above their competitors, with an overall aesthetic to match.

"You have good people in the marketing department at Target, and they have really good designers who have created such an ambient atmosphere for people. It's really well-lit at Target, right? There's a lot of color at Target. It's pretty consistent throughout the store and generally that's going to make people feel happier," he explained to Refinery29.

Happy people, Chapman added, are more likely to spend money.

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Tom Meyvis, a professor of marketing at New York University's Stern School of Business, said that because Target sells pretty much everything under the sun, it has the ability to be especially clever with the placement of things (like the Pepto Bismol next to the hot sauce) to drive purchases.

And now for the real kicker: "psychological pricing." Pricing things at $9.99 as opposed to just rounding up to the $10 is a prime example of this. As Chapman pointed out to Refinery29, putting a nine at the end of a price makes us feel like a product is on sale even when it's not.

But in the end, it all comes down to trust. Target shoppers truly believe that they're getting good prices, making them more willing to part with their hard-earned dough.

And according to Mayvis, it's not so much that stores like Target "trick" us into buying more, it's that they point us in the direction of things we hadn't considered—things that ultimately make us happy.

"I don't want to say that the stores are making us buy things that we don't want, that we don't need," he concluded. "These unplanned purchases are often things that we do like and that we do want. We just didn't think of them."