> research done by Barry Schwartz and later by Sheena iyengar

Per the article, Sheena Iyengar did the study on 2000 and then ”This study became a central example in Barry Schwartz's 2004 book, The Paradox of Choice.”

On a related note, this is one of the main reasons we like Costco. Fewer SKUs means less cognitive load and easier shopping.

Thinking about it, my local Costco has a huge coffee selection... one side of a whole isle. Only coffee gets that treatment!

I'm not sure this imagined scenario, where coffee shops ask where you want your beans from, would apply to this study:

"displayed 24 jams in a busy supermarket for tasting...60% of customers stop[ped and tasted], 3% [made] a purchase."..."Next, 6 jam jars....[40% stopped, less than 60%], but...purchases went up [from 3%] to 30%."

It reeks of the worst sins of early-TED-era social psychology experiments: tons of obvious confounders.

For instance, 24 samples at a table that was 50% busier means I'm thinking I'll come back and wrap up my tryout next week or whenever: it's very busy and I can't afford 15 minutes to sit around trying to maintain tasting notes on something I didn't have intent to buy anyway -- if I did, I wouldn't be sampling!

It also means less 1:1 salesmanship contact with the purveyor of samples, and 4x of much investment needed on their part.

It also depends on how popular the place is, and the customer demographic. Continuing with that example, if it's a small grocery store in a town with a population of a few thousand people, sure, there's definitely no point in having 24 different types of jam. However, if it's a store specializing in jam, in a large city, then having a larger selection makes sense, especially when you have someone working there who you can ask to recommend something. Sadly that usually also implies higher prices.