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Store Monitoring

A price typo doesn’t look like an error. It looks like a sale.

Pricing mistakes are the quietest expensive failure in ecommerce. Nothing breaks, no page errors, no support ticket — the store simply sells at the wrong number, often faster than usual, until someone notices the margin. These are the ways prices go wrong on a Shopify, WooCommerce, BigCommerce or Wix store, how to fix each one, and how to make sure the next one is caught the same day.

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The seven ways a price goes wrong

Almost every pricing incident traces back to one of these. Notice that only one of them is a person typing a wrong number.

  • A bulk edit applied to the wrong collection or the wrong filter — the single most common cause, and the one that changes the most variants at once.
  • A CSV import with a shifted column, a decimal separator mismatch, or blank cells that overwrite prices with zero.
  • A repricing or discount app behaving unexpectedly after an update, a rule change, or an expired campaign.
  • A sale that ended without the compare-at price being cleared, leaving a permanent “was $X” that is no longer true.
  • An inverted sale: compare-at set below the selling price, so the store advertises a discount that is really an increase.
  • Multi-currency rounding or a stale exchange rate, so one market’s prices drift away from the others.
  • Stacked discounts — a code, an automatic discount and a sale price all applying to the same order.

How to fix each one

Fixing is usually fast. Finding out is the slow part, which is why the last step matters more than the others.

  1. Establish what changed and when. Compare current prices against a known-good snapshot rather than against memory — without a snapshot you are reconstructing history from order data.
  2. Fix the zero and negative-margin prices first. A $0 or near-zero price converts fast and is the only category where minutes matter.
  3. Clear inverted compare-at prices next. They are both a margin problem and, in several jurisdictions, an advertising-standards problem.
  4. Re-run the bulk edit correctly on a filtered selection, and verify against a handful of variants at each end of the range before applying.
  5. Audit the app that caused it. If a repricing app made the change, turn off the rule before fixing the prices, or it will re-apply them.
  6. Put a daily price-diff in place, so the next occurrence is a notification rather than a discovery.

How Cassian™ classifies a price change

Not every price change is an error — most are intentional. Useful monitoring is therefore about severity and grouping, not about reporting every difference.

What changedSeverityWhy
Price set to $0CriticalSells immediately, at a total loss
Compare-at below selling priceCriticalAdvertises a discount that is an increase
Change greater than 50%HighRarely deliberate at this size
Change of 10–50%MediumPlausibly a sale, worth a glance
Change under 10%LowUsually intentional
20 or more variants in one runGroupedReported once as a bulk change, not twenty times

Preventing the next one

Prevention is mostly process, and it is cheap. Filter before you bulk edit and read the count before confirming. Export the current prices before an import, so you have a rollback. Keep repricing rules to as few apps as possible. And schedule the end of a sale at the same time you schedule its start.

What Cassian™ actually does

Specific checks, with the plan they run on.

Cassian Sentinel™ pulls your full catalog through your platform’s admin API and compares every variant’s price against yesterday’s snapshot.

Every plan with a connected store. Scheduled daily on Protector and above.

A $0 price or a compare-at price below the selling price is classified critical; changes above 50% are high, 10–50% medium, and under 10% low.

Critical only on Inspector; all severities on Analyst and above.

Twenty or more changes in a single run are grouped and reported as one bulk change, so a legitimate repricing does not produce hundreds of alerts.

Protector and above.

Full price history is retained per variant, so “when did this change, and what was it before?” is a lookup rather than an investigation.

Every plan with a connected store.

Price monitoring works on Shopify, WooCommerce, BigCommerce and Wix — the check reads each platform’s own admin API rather than scraping the storefront.

Every connected platform.

FAQ

Common questions

How do I find price errors on my Shopify store?
Compare today’s prices against a known-good snapshot rather than reviewing products by hand — a catalog of any size makes manual review unreliable. Look first for zero prices and for compare-at prices set below the selling price, then for changes above 50%, then for anything that changed in a batch you did not intend. Cassian™ does this automatically: a daily catalog snapshot, a variant-by-variant diff, severity classification, and bulk changes grouped into a single alert.
What causes prices to change without anyone changing them?
Usually an app. Repricing apps, currency converters, discount apps and subscription apps all write prices, and a rule that changed or a campaign that expired can move hundreds of variants with no human involved. Multi-currency rounding is the other common source — a stale exchange rate drifts one market’s prices away from the rest without a single edit.
Is an inverted compare-at price actually a problem?
Yes, on two counts. It misrepresents the discount to the customer, and advertising a “was” price that was never the selling price is regulated in most markets — the UK, EU, Australia and New Zealand all have rules about it. Cassian™ treats an inverted sale as critical for that reason, not just as a formatting mistake.
How fast will I know about a price error?
On Protector and above, the catalog snapshot runs daily on a schedule, so a change made today is reported on the next run. On Inspector and Analyst the comparison runs with each scan instead of on its own schedule. Either way it is same-or-next-day, rather than at month end.

Keep reading

Store Monitoring Pricing Pulse — price anomaly detection Store Health Checklist Signs You’re Losing Sales Cassian™ for Shopify Pricing

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