Most "Performance management systems" are based on hierarchical organizational goals which function on and around a financial calendar. This has created an illusion that performance management is all about the results. Well its true that results achieved define your past performance but what makes them is the efforts,mindset and capabilities. So a result based performance management system is designed to help managers doing a post incidental postmortem of a dead body instead of actually proactively managing team performance.
These systems assign a carrot to the result and expect the entire workforce to find it tempting enough to break their behaviors. The appraisal cycle comes the stick which has little or no impact on the past or future performance. Why you ask? well its simple neither the carrot or the stick is associated with actual efforts. By the time you get to the results its like sitting for an exam and knowing that you were under-prepared only at the day you got the results ; not when you were preparing for it, not even when you were giving the exam but at the very end when its all lost and all that you can do is say if only I knew before and try to move on.
Unlike traditional methodologies OKR provides a much more objective way of managing organization goals. Organisation goals are broken into department objectives with are measured based of results and the these objectives are then broken into a series of tasks which when executed will give the key results required to achieve the goal. Tracking the tasks and results relationship allows managers to take real time decisions of what more/less/different can be gone to increase the probability of achieving the set time bound goals. Plalyfe's product catalyst uses the same approach in its activity and objective game design framework.
A sales rep gets a set number of points for doing every activity and a set number of points for achieving a key result so that both sales managers and sales reps can measure,track and manage both task undertaken and results achieved in real time to make more pro-active decisions and focus on successful behaviors.