In Unleashed, each product will have a min and max limit for each warehouse. If the available stock is outside of this quantity, then it will display a stock alert. In AIM, the rate of demand and your strategy for how many days of stock you want to hold will determine the min / max stock limit. 
For example, if you sell 28 units a month of a product, and you want to hold 1-4 weeks of stock, then AIM will update the min limit to 7 units and the max limit to 28. This is intended to be used with the Reorder Report to help trigger replenishments when the low limit is reached.