The backlog is used to record, track, and prioritize remaining work items.
A backlog occurs when the volume of work items to be completed exceeds the capacity to complete them.
In a managed backlog, the items at the top have the highest business value and the highest priority. These are normally the next items to be selected to be worked on.
Periodic review of the entire backlog should occur because changes in stakeholder needs and priorities may necessitate changes to the priority of some of the backlog items. In many environments, the backlog is reviewed at planned intervals.
The changes to the number of items in the backlog are regularly monitored. The root causes for these changes are investigated: a growing backlog could indicate an increase in demand or a drop in productivity; a declining backlog could indicate a drop in demand or improvements in the production process.
There may be more than one backlog. For example, one backlog may be used to manage a global set of items, while a second backlog may be used to manage the items that are due to be worked on within the very near future.