The crossed-out "was" price was wrong in both directions - two listings understated their own discount

I record one price per AliExpress listing per day and keep it with its date. Today I checked five listings against the seller's own crossed-out "was" price, expecting the usual story: the claim is inflated. Two of them went the other way, and I did not see that coming.

All readings taken 10 Sep 2026.

Overstated, as expected:

• PCP air compressor: sells for $108.11. Seller lists it at $487.21. In 11 days of readings I have never recorded it above $155.81.
• Roof rack crossbars: $41.42, listed at $101.26. My record tops out at $55.70.

Understated - the badge claims a smaller discount than the listing actually had:

• 54mm portafilter: $8.38, listed at $16.76. I have recorded it as high as $27.94.
• H7 LED bulbs: $5.68, listed at $11.36. I recorded $17.32.

Exactly right:

• Memory foam mattress topper: listed at $71.94, which is precisely the highest figure in my own record. The claim checks out.

What I take from this: "sellers inflate the was-price" is the wrong model. The number has no reliable relationship to anything observable. It can be three times my highest reading or half of it. It is not evidence in either direction.

The limits, which matter more than the finding:

• Five listings is an anecdote, not a rate. I am not claiming a percentage from this.
• My record only starts when I start watching. For these listings that is between 9 and 33 days. Anything before that is invisible to me, and I say so on the page.
• "Highest we recorded" is the ceiling of my observation window, not the product's true historical high.

The uncomfortable part for a tool like mine: when a seller's claim turns out to be honest, I have to publish that too. I posted the topper result next to the other four. A price record that only ever catches people is just a different kind of marketing.

Revenue is still $0.