The missing component necessary to finish this user story is why because it describes the benefit or value that sales reps will get from having visibility into their pipeline revenue (such as forecasting sales performance or identifying opportunities). The who part of this user story is "sales reps" because it describes the user role or persona who will benefit from this feature or functionality. The what part of this user story is "visibility into sales rep' pipeline" because it describes the feature or functionality that sales reps want or need.