Use both turnover and absence, and you've improved the quality of the indicator. Add quality of goods produced, variability in productivity, and timekeeping, and you've improved it further. It is self-evident, I think, that it's better to sample all of the ideals if you can. The result, otherwise, is to channel performance into those ideals which the performance indicators point to. I can offer an example from academia.
Many academics therefore seek to achieve as many publications as possible from each study.
You might reasonably argue that the outcomes would be better if they put more of their effort into doing their research, and reported it as economically as possible. If you omit intended effects, you're ignoring the indicators which usually point most directly to the ideals. If you omit either of the others, you make it easy for people to lift apparent performance by increasing unintended effects or by consuming more resources. In fact, sometimes those are the only indicators that are accessible enough in the short term to be feasible. But there is a trap in their use.