# Testing a Low-Stock Message on a Product Page

Page: https://alidemirbas.com.tr/en/lab/ab-test-library/tests/testing-a-low-stock-message-on-a-product-page

## Hypothesis

If the page shows the current stock count once a product meets the stock rule, shoppers may stop putting off the decision so they do not miss out. On eligible products, purchase conversion rate (CR) could climb, though the sense of pressure could also push cart abandonment up.

## When to run this test

Add-to-carts with no return visit, people coming back to the same product page again and again, or support tickets about low-stock items selling out without warning point to shoppers who like an item but put off the decision. If the message works, purchases on products that meet the rule happen sooner and cart abandonment does not climb. If the delay comes from price or shipping terms, look at those first; if live stock data is not reliable, fix that, and show the message only when the predefined stock rule is met.

## Primary metric

**Purchase conversion rate (CR)**: Compare purchases per assigned visitor for products that meet the predefined stock rule.

## Other metrics

- **Add-to-cart rate**: Check whether shoppers take the first purchase step.
- **Cart abandonment rate**: Track abandonment in the same session window; do not assume pressure will be harmless.
- **Return rate**: Track returns over the same period; a return does not prove the purchase was rushed.
- **Time to purchase**: Measure time to purchase separately from conversion.

## What to check before and during the test

- **Message**: Show a fixed message based on live, accurate stock data.
- **Placement**: Choose one placement and keep it fixed.
- **Design**: Keep the chosen color and visual emphasis unchanged.
- **Eligibility**: Use one predefined stock threshold; do not alter the displayed count to test the threshold.
- **Category**: Review category differences within the same setup.

## What to watch when reading the result

- Use purchase conversion rate (CR) per assigned visitor as the yardstick. If add-to-cart rises while cart abandonment rises too, the message may be creating pressure that drives shoppers away, and a small lift in conversion is then no reason to ship. Conversion rate does not measure decision speed, so read time to purchase on its own.
- Present the message without alarm-red styling and without letting it outrank the price or the CTA; otherwise you are measuring visual pressure, not stock information. Review category differences within the same setup, and do not carry the result beyond this threshold and placement.
- Compare returns once both arms have had equal time; a rise in returns does not by itself prove purchases were rushed. Because the message appears only on products that meet the rule, the sample may stay small. Before launch, get the visitors per arm needed for the lift you care about from the [sample size calculator](https://alidemirbas.com.tr/en/calculators/sample-size-calculator) and divide it by those products' daily traffic per arm to see the run length.

## Frequently Asked Questions

### Which products should show a low-stock message?

Use the fixed eligibility threshold and live inventory. Do not alter displayed quantities to manufacture urgency. Preserve the same stock-data basis.

### Does conversion show that decisions became faster?

No. Use purchases per assigned eligible visitor as the primary outcome and measure time to purchase separately.

### How should a low-stock message be written?

State genuine, current availability without invented urgency. Preserve price and CTA visibility. Use direct feedback to investigate pressure or misunderstanding rather than inferring those feelings from behavior alone.

### Do more returns prove purchases were rushed?

No. Compare returns over equal windows and examine conversion and relevant categories. Individual motivation cannot be established from return counts alone.