Once the review is created, the goals have been added, measurements, weigh on goals has been assigned it would be very useful to lock it for editing/deleting from the employee (and potentially manager) side. Currently, employee can change target measurement, change weigh assigned to goals etc without audit trail for managers/HR. This can also be applicable for goals (or at least to have some supervision that for example if I as an employee make some changes to a goal/review manager/HR is notify about that)