Amazon does make you pay to use the warehouse space. If your inventory is not selling, they start charging you for housing the inventory. Their ideal scenario is to force sellers to send inventory that matches sales so warehousing is optimized.

I thought we paid for warehousing regardless. Though I think there are situations where if your selling inventory is turning over quickly, they may waive warehousing fees. The incentive is definitely there to manage inventory at optimal levels.

If your inventory sits too long in their warehouse, the fees go from "regular" storage fees to "long-term" storage fees. Those fees are much higher, which incentivizes the seller to put the stuff on sale to blow it out of their warehouses, or you can have the inventory sent back to you.

Also, fees vary by category and season. Around the holidays, you'll see them making a push to increase long-term storage fees to make way for the stuff that will actually sell, and on categories which are hot for the holidays, you might see them providing incentives with lower storage fees.

I'm not the primary person that deals with Amazon FBA, but he sits next to me. Don't take what I'm saying as the gospel, but this is based on somewhat second hand experiencing and reading some of the emails that come through. My partner pays more attention to those details.

Yes I was talking about the long term storage fees which they used to charge if inventory was rolled over after 30 days. The items we used to sell needed to be purchased in high quantities to get a decent price so we would ship items to FBA on a monthly basis trying to estimate demand. Eventually, Amazon itself started selling the same item and it just wasn't worth it especially with higher fees for FBA.