I tell all my DRs that, at the end of the year, I will evaluate them on their (self-assessed) 3 most impactful things they've done that year with a 60%, 30%, 10% weighting.
There's a couple of different ways of optimizing towards that goal, you can try out a lot of little projects and double down on the ones that seem like they're working or you can do a careful analysis and scope out a few things you think will be a big hit.
In truth, there's no ability for me to evaluate them to that level of precision, the framework is mainly there to foster two skills I regard as vitally missing:
1. Ruthless prioritization. One of my frequent questions is "does this sound like the 4th most important thing you'll do this year? If so, why are you doing it?". Being able to cut down on the noise and really focus is hard for people, especially when they feel like there isn't a permission structure in place for it to happen. Even with an explicit focus in place, the norms of the workplace make clearing away time for deep thought preciously valuable.
2. Owning of measurement of impact. Being able to measure a thing is, I believe, in many ways more important than doing the thing in the first place. Measuring forces us to ask hard questions that we often skip over: What metrics am I hoping to affect via this project? How does this metric tie into the larger goals of the company? Are we measuring this metric already? If not, how do we start? What change in this metric would count as impactful vs other projects I could be doing?