The hidden cost of buy-box loss: why your velocity lies

Most reorder formulas start with 30-day velocity. Which is fine — until you lose the buy box for two weeks and your "velocity" craters by 60%. If your reorder tool trusts that number, you're about to order too little of a SKU whose real demand is stronger than ever.

The quiet failure mode

Buy-box loss compresses observed sales. Competition intensifies (a reseller undercuts you by $0.20) or Amazon decides your listing needs a price-parity check. Either way, your listing still gets impressions — you just stop converting them.

If your reorder formula is avg_daily_sales × target_days_of_supply, it reads the compressed sales as lower demand, reorders proportionally less, and then when you win the buy box back, you stock out.

The reverse is just as dangerous. You're on sale, you own the buy box for a month, your observed velocity spikes, and your reorder tool orders for the spike as though it's the new normal.

What the purchasing agent does instead

When the BuyCast.ai purchasing agent reads velocity, it reads it alongside the buy-box rate for the same period. If you owned the buy box only 40% of the time, it divides your observed velocity by 0.40 to estimate what demand would have been at full buy-box ownership. It then forecasts against the adjusted demand series, not the observed one.

This is off by default for Starter accounts (we keep their logic conservative) but on by default for Growth and Pro.

When to turn it off

If you're running deliberate buy-box-loss periods as a pricing experiment, you don't want the agent to correct for it — that would double-count your intentional price change. In those cases, flag the period as intentional in the repricer log and the agent will skip the correction.

The meta lesson

Your velocity isn't a demand signal. It's a "demand × your conversion conditions" signal. Separate the two, and your reorders stop whiplashing.