Dynamic pricing is going to drive us crazy

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"How much does this cost?" has become a surprisingly complicated question.

The rise of e-commerce, algorithmic pricing, and black-box systems has left consumers feeling like they're playing roulette when they buy something.

To show how unpredictable the process can feel, BI's Juliana Kaplan conducted an experiment. She tracked price changes over 14 days for a handful of items she left in her digital Old Navy cart. The prices fluctuated so much that Juliana dubbed herself a "leggings day trader."

It's not the first time BI has tried to uncover the quirks of online pricing.

A few weeks ago, BI's Peter Kafka and Emily Stewart wrote about a Big Mac experiment we conducted at the office. A group of us, myself and Juliana included, ordered the same thing from the same McDonald's at the same time on Uber. Some of us were charged slightly different fees. (I took part in this one and came out on the higher end. Not fair!)

The difference in fees wasn't massive — about 20 cents — but enough to make us wonder what was going on. When Peter and Emily reached out to Uber, they essentially shrugged.

Juliana got a similar response when she asked Mark Tremblay, an assistant economics professor at the University of Nevada, Las Vegas, about the best time to pull the trigger on her volatile shopping cart.

"If I knew that, I wouldn't be talking to you, and I'd be investing in stocks, right?" Tremblay, who studies the digital economy, said.

Dynamic pricing's biggest impact might not be on your wallet.

Paying an extra quarter for a Big Mac probably won't bankrupt you. Constantly wondering if you're getting screwed on a price is the kind of mental debt that's hard to shake.

It's why ordering takeout for me has gotten exhausting. Which ordering app should I use? Who's offering the best coupons? Which one has the lowest fees? Should I order directly from the restaurant? Is it worth picking it up instead of getting it delivered?

More than once, I've gotten so fed up that I just cooked something at home.

The anxiety that comes with big-ticket items is worse. I can't tell you how much I hemmed and hawed over buying a washing machine on Black Friday.

You've heard of FOMO. I call this FOMAD: fear of missing a deal.

You might welcome the chaos. Dynamic pricing goes both ways, you argue. It's just about timing it right.

If that's the case, I'd like to learn the rules. Too often, the game ends with me eating cereal in my kitchen.