An inventory system where counts are performed continuously, often eliminating the need for an annual overall inventory. It is usually set up so that A items are counted regularly (i.e., every month), B items are counted semi-regularly (every quarter or six months), and C Items are counted perhaps only once a year.

Inventory Counting 101: Your Simple Guide to Better Stock Management
Running an ecommerce business? Then you know inventory is everything. But here’s the question: do you actually know how much inventory you have right now? Many business owners think as long as they have enough products to sell, the exact count doesn’t matter. That’s a costly mistake. Accurate inventory counts