Merchandising
Myth:One hero image and a spec table is enough.
Evidence:Shoppers rely on image sets to answer objection questions; scale, in-use and detail shots reduce returns as well as lifting conversion.
Image quantity without variety adds page weight and no comprehension.
Baymard Institute · 2023 · Primary Research
Channels: ecommerce · web
The Validity Gap
Myth:A big enough A/B test or attribution platform can pin down each campaign's ROI.
Evidence:Across 25 large field experiments with major U.S. retailers and brokerages, the median confidence interval on ad ROI was over 100 percentage points wide; individual-level sales are so volatile (coefficient of variation ~10) that an informative test often needs 10M+ person-weeks.
Checkout
Myth:Long checkouts are fine if the product is good.
Evidence:Average large-site checkouts ask for far more fields than necessary; trimming to the minimum viable set is one of the highest-yield conversion changes available.
The Validity Gap
Myth:Display ad ROI shows up in online conversions.
Evidence:A randomized experiment with 1.6 million Yahoo! users found display ads profitably lifted a major retailer's purchases by 5% - but 93% of the increase happened in brick-and-mortar stores, and 78% came from customers who never clicked the ads.
Checkout
Myth:Forcing account creation builds your CRM.
Evidence:Mandatory account creation is a top-cited abandonment driver; guest checkout with a post-purchase account offer captures both revenue and the record.
Retail Media
Myth:Retail media ROAS proves the channel works.
Evidence:Most retail-media ROAS counts sales that would have happened anyway; even incremental ROAS is so methodology-sensitive that Ovative, Albertsons Media Collective and Kellogg faculty built a framework just to standardize it.
One crib in your inbox every Monday. No spam, unsubscribe anytime.