While finalising your OKR tool ensure that it provides some kind of data to help you monitor OKR adoption. One of the easiest metric to track is frequency of progress updates. If employees are updating their OKRs on a frequent basis (at least once in couple of weeks), you’ve got a good start. For the ones who are not updating as frequently, try to open a dialogue with them to understand their obstacles. More often than not, these are systemic/procedural problems than employee motivation.
Below is the list of some easy to track metrics for monitoring OKR adoption –