Over a century ago, a copywriter named Maxwell Sackheim was wrestling with a problem every Amazon seller knows: how do you get busy people to actually pay attention? He was trying to sell a mail‑order English course and tested headline after headline, but most of them just didn’t pull.

Then he wrote a new one: “Do you make these mistakes in English?” It became one of the most famous ad headlines in history and ran profitably for around 40 years, beating every challenger they tested against it.

Here’s the interesting part. They also tried versions like “Do you make mistakes in English?” Same basic idea, but missing one small word: “these.” That tiny word completely changed how readers responded.

That one word turned a simple question into an open loop their brains wanted to close. It created just enough tension and curiosity that readers felt almost pulled into the rest of the message.

This same idea works beautifully in your Amazon emails and buyer messages today. A subject line like “Big sale this weekend” gives everything away — there’s no mystery, so there’s no real reason to click. A

line like “We’re pulling 3 products from the store on Friday” instantly raises questions in your customer’s mind: Which products? Are they favorites? Why are they going away? and that curiosity nudges them to open the email to get the answers.

The difference between a subject line people ignore and one they can’t resist often comes down to what Sackheim discovered a century ago: give your audience enough information to care, but hold back just enough that they feel compelled to read on.

For Amazon sellers, this is a template for every message your customers see.

When you write ad headlines, don’t just say “20% off our bestsellers.” Try something like “These 3 bestsellers just dropped 20%” so shoppers feel compelled to see which products made the cut.

For infographics on your Storefront or A+ Content, avoid flat titles like “How our product works.” Instead, use a line such as “3 mistakes this product prevents” so the graphic itself promises to answer a specific question.

For email subject lines and buyer messages, skip “Update about your favorite products” and go with “We changed 2 things about your favorite product” so curious customers open to find out what changed and why it matters to them.

Across your Amazon presence, the principle is the same: make every headline, graphic title, and subject line open a loop in your shopper’s mind, then let your content close it.

Workmagic recently reported some interesting findings from a study they did.

A party games brand suspected their TikTok ads were driving sales way beyond TikTok Shop, but they couldn't prove it. Platform dashboards only showed what converted on TikTok itself, leaving Amazon, Walmart and Target sales completely invisible.

The Test: They ran a geo lift test (pausing ads in certain markets and comparing against markets still running ads) to measure TikTok's real incremental impact across all their sales channels.

What They Found: Only 37.5% of TikTok-driven sales were actually happening on TikTok Shop. The other 62.5% were converting on Amazon and retail stores. That's a massive "halo effect" that traditional attribution completely missed.

The Numbers That Matter:

Their incremental ROAS jumped from 0.8x to over 2.0x once off-platform sales were counted, a 166% improvement. Cost per acquisition dropped 68% when they factored in those hidden conversions. And in the 30 days after the test, they scaled TikTok spend and saw a 64% increase in total sales while actually improving efficiency by another 24%.

The Takeaway for Amazon Sellers: If you're running TikTok ads and only measuring TikTok Shop performance, you're likely massively undervaluing the channel. A big chunk of the demand TikTok generates is converting on Amazon.

Customers see it on TikTok, then go buy it where they're most comfortable (called the ‘halo effect’). This is worth thinking about before you cut a TikTok budget that looks unprofitable on the surface but is quietly feeding your Amazon sales.

If your product is one of the unlucky ones that gets a “Frequently Returned” badge, which in effect kills conversion, it just got worse.

Now Amazon is recommending your competitors who are NOT as frequently returned right on your ASIN under your title!

Time to make damn sure you solve any issues causing high returns on your SKUs, or just go ahead and kill the product and move on.

Amazon's "Great Compression": Fewer Sellers Control More GMV Than Ever Source: Marketplace Pulse

The concentration of power on Amazon is accelerating fast. Fewer than 7,760 sellers now generate half of Amazon's U.S. third-party GMV. That’s just 1.6% of the active seller base. That's down from 15,000 sellers holding that same 50% mark less than three years ago.

The numbers get even more striking at the top: 111 sellers produce 10% of third-party GMV, and 1,020 sellers account for 25%. Meanwhile, roughly 500,000 sellers are active in the U.S. marketplace, but 80% of them are splitting just 10% of total revenue.

What's driving this? Marketplace Pulse calls it the "Great Compression" — rising fees, tariffs, and ad costs are squeezing out sellers who lack the operational sophistication and capital to compete.

The sellers who remain at the top aren't just surviving; they're capturing a bigger share of a growing pie. Average revenue per seller in the top cohort has more than doubled to nearly $20M/year.

U.S. vs. Chinese sellers at the top: U.S. sellers make up 55% of the top ~7,760 but control 67% of that cohort's GMV. Chinese sellers represent 41% of the group but generate 30% of the GMV, meaning American sellers have significantly higher per-seller revenue at the top.

Every seller in this elite group exceeds $5M in annual sales, with some surpassing $1B on the platform.

The takeaway: Amazon's marketplace is maturing into a power-law economy. Scale, capital, and operational excellence aren't just advantages anymore, they're table stakes for the top half of GMV.

You or someone on your team really should be at ECOM MASTERY AI featuring BDSS in Nashville this April. You’ll learn what you need to do in a new omni-channel world to stop relying on just Amazon (and you’ll learn how to maximize that too).

✌🏼 See you again Thursday …

The answer to today’s STUMP BEZOS is
69% was driven by third party sellers