Doorbuster? Or tag sale?

That’s the question many Amazon (AMZN) customers seem to be asking as they browse the retail site during a shopping extravaganza Amazon has hyped as bigger than Black Friday. Prime Day, as Amazon calls it, is supposed to be a mid-summer opportunity to get killer prices on some of the year’s hottest products. But many shoppers are logging on to find underwhelming deals on oddball offerings such as beer coolies, nose vents, shoehorns and cat-training aids.

Given Amazon’s heft, some retail analysts have speculated that the online dealfest could reshape the whole retail landscape. Instead, Prime Day seems to be shaping up as a flop, as social media posts such as those posted below suggest.

Since Walmart (WMT), Amazon’s biggest competitor, vowed to match Amazon’s deals with “rollback” specials of its own, Yahoo Finance decided to quickly rank each retailer in 4 categories, to determine which wins the first annual Prime Day slugfest. In our estimation, Walmart walloped Amazon, by a score of 14 to 8 (with 20 being the highest possible score). Here's our grading system:

Amazon characterized Prime Day as a success, boasting in a press release that order rates halfway through the day exceeded those during Black Friday, the day after Thanksgiving, in 2014. Among the day's sales leaders, according to Amazon: a Kate Spade purse that sold out in less than a minute, a set of Rubbermaid storage containers for $14.99 (28,000 sold), and a 50-inch Samsung 3-D TV for $999 (1,200 sold).

Still, the come-and-go deals required shoppers to monitor the site for hours or join a waiting list for "upcoming" offers, which seemed to frustrate many users. Here's our review of Prime Day during the first half of the day, in the four categories we graded:

Relevance. Walmart offered a lot of mainstream products typical families can use, while Amazon offered a strange collection of miscellania that could have come from some gigantic leftover bin. Among Walmart’s top rollback specials, for instance, were paper towels, toilet paper, diapers, mattresses, sheets, a stroller, a crib, TVs, smartphones, printers and a lot of women’s clothing. You know, stuff people use every day.

Amazon listed everyday items too, but it took longer to find them. When we spot-checked its top listings, for example, we found useful gadgets such as a router and digital camera, plus lots of smartphone cases and charging cables. But the same check also offered a baffling array of bottom-shelf items, such as a thermal laminator, a turmeric curcumin dietary supplement, anti-callus gloves, a rifle scope and many other specialty products. Amazon offered thousands of “lightning” deals that came and went during the day, so shoppers logging on at different times would see different offerings. In general, however, offbeat items seemed to outnumber everyday products. (But "Fifty Shades of Grey" fans are in luck: the unrated Blu-ray and DVD could be yours for $13.99.)

Name brands. During our half-day check, Walmart had popular branded products such as RCA TVs, Apple iPads, Samsung phones, HP laptop and Luvs diapers, along with some off-brand clothing and household items. Amazon offered its own Kindle products and a few well-known brands such as Nikon cameras, HP printers and GoPro bundles, but also a lot of other makes consumers won’t recognize, such as these brands of headphones: Jarv, Wicked, August, Blurex and Tweeds. Bose isn’t exactly quivering.

Price. Savvy online shoppers won’t be surprised to hear that while both sites offered good deals, both also overstated the savings. Walmart, for instance, offered a 55-inch RCA HDTV for $399.99, claiming that was half off the regular price of $799.99. But Amazon offers the same TV for $495.78 (which is not a Prime Day lightning deal). And Amazon offered a Black & Decker dust buster for $47.99, claiming that represented a savings of $78.01 off the regular list price of $126. But Home Depot sells the same product for $74.99.

Shopping experience. Amazon’s lightning deals might appeal to dedicated shoppers who enjoy the sport of waiting for deals to materialize on stuff they actually want, and have nothing else to do on a Wednesday in July. But it’s a mystery why Amazon played this sort of game with shoppers instead of just letting everybody see all the sale items all at once (and without a countdown clock telling shoppers how long they had to buy). Walmart’s old-fashioned strategy—post all the deals, all day long—was the winning approach, at least for shoppers who want to buy what they need, save a few bucks and get back to work. If there’s a Prime Day 2 (and it’s a safe guess there will be), we're betting Amazon’s deals may look a little more like Walmart’s.

Editor's note: This story has been updated to include new information provided by Amazon in a press release, including details on order rates and sales figures.

Rick Newman’s latest book is Liberty for All: A Manifesto for Reclaiming Financial and Political Freedom. Follow him on Twitter: @rickjnewman.