> 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!