To see the statistics of how a consultant is assigned or rejected a role in a project you should update and maintain the status of the roles. You can state why the consultant was rejected for a role.
Click on the role in the Overview
You get to the role overview. Here you can add several information. If you have preliminary assign consultants it is possible to assign or edit. When you edit the role it is possible to change status for the role.
In the edit function, work with status or change team selected for this role for the consultant.
You can collect the statistics via the export All projects and roles -> Administration - Exports