KPI data measures what was delivered. Ratings measure how. Learn how to combine KPI outcomes with ratings using a practical weighting framework.
Marketing Lead
May 20, 2026
•
4 Mins Read
Knowing how to combine KPI outcomes with ratings is one of the most consequential design decisions in performance management. Two employees can deliver identical KPI results — one by burning out colleagues and missing handoffs, the other by coordinating well and elevating the team around them. If your rating is derived purely from KPI completion, both employees receive the same score. That is an accurate measure of output and a completely inaccurate measure of performance. This article explains how to weight, calculate, and calibrate a blended rating that captures both what was delivered and how.
If your rating is derived purely from KPI completion, both employees get the same rating. That is an accurate measurement of output and a completely inaccurate measurement of performance.
The challenge of combining KPI outcomes with behavioural ratings is one of the most important design questions in performance management. Get it wrong in one direction, and you produce ratings that reward activity over impact. Get it wrong in the other, and you produce ratings that reward likeable behaviour over results. This article explains how to get it right.
Performance has two dimensions that must both be assessed:
According to research from Workitect on competency-based performance management, in operational or line roles achievement of performance results may be weighted up to 90%, with competency behaviours at 10%. In service or leadership roles, the balance shifts toward 50/50. The right weighting depends on the role.
The key principle: neither dimension can be zero. A rating system that only measures KPI outcomes rewards output that damages culture. A system that only measures competencies rewards professional behaviour that delivers nothing.
| Role type | Example roles | Outcome weight | Competency weight | Notes |
|---|---|---|---|---|
| Operational/delivery | Sales, engineering, finance analyst | 70-80% | 20-30% | Output is measurable and directly valued; competencies ensure sustainability |
| People-facing/service | Customer success, HR, communications | 50-60% | 40-50% | How the work is done directly affects the outcome quality |
| Leadership/management | Team leads, department heads | 50% | 50% | Output is team performance; competency is how the team is developed and led |
| Administrative/support | Operations coordination, executive support | 40-50% | 50-60% | Outputs are harder to quantify; behaviour quality drives most of the value |
Once weightings are defined, the calculation is straightforward:
Example: a sales manager with a 70/30 outcome/competency split. KPI achievement: rated 4 out of 5 (80%). Competency rating: rated 3 out of 5 (60%).
The blended performance rating calculation is: (4 x 0.7) + (3 x 0.3) = 2.8 + 0.9 = 3.7 out of 5, or approximately "exceeds expectations."
Without the competency component, the rating might have been 4 (above the actual blended score). The competency weight correctly brings it down to reflect that the method of delivery was average even if the results were strong.
Talstack's Performance Reviews module allows HR to define both KPI-linked and competency-based rating dimensions within a single review form, with customisable weightings by role type. The Goals module tracks OKR progress throughout the cycle, so the outcome dimension of the rating is populated from documented data rather than reconstructed from memory.
The Competency Tracking feature supports consistent behavioural assessment across managers, with defined indicators at each competency level. Together, these features produce a blended rating that reflects both what was delivered and how.
This is a common problem in African organisations where OKRs are set as a process formality rather than as genuine performance anchors. In that case, HR and the manager need to apply more weight to the competency and quality dimensions and use manager narrative to contextualise the KPI data. The solution to poorly designed KPIs is to design better ones for the next cycle, not to ignore the outcome dimension entirely in the current one.
KPI outcomes tell you what happened. Competency ratings tell you why and how. A blended rating that weights both, appropriately for the role, produces a performance record that is accurate enough to inform development, succession, and compensation decisions without reducing a person's entire contribution to a single number that only captures part of the picture.
