You have activated the workflow for confirmation variances in SAP Project System.

The receiver of the workflow item for confirmation variances in SAP Project System is the person responsible for the network activity. A workflow item is a function that allows you to automate and monitor business processes in SAP systems. A workflow item can be triggered by various events, such as status changes, deadline monitoring, or variance analysis. A confirmation variance is a difference between the planned and actual data of an activity or an activity element, such as dates, durations, work, costs, and so on. A confirmation variance can indicate a deviation from the project plan or a potential risk for the project completion. The receiver of the workflow item for confirmation variances in SAP Project System is the person responsible for the network activity. The person responsible is a partner function that identifies who is in charge of an activity or an activity element. The person responsible receives a workflow item when a confirmation variance exceeds a predefined threshold that is defined in Customizing for Project System under Confirmation Define Confirmation Parameters . The person responsible can then review and analyze the confirmation variance and take appropriate actions to resolve it. Reference:https://help.sap.com/doc/0f069b2e08b748f1b480d4c8b46c3c49/100/en-US/f373bb53707db44ce10000000a174cb4.html