would there be a specific metric (e.g. estimated QALYs saved) or would donors construct individual conversion rates (at least implicitly) based on their evaluations of how effective charities are likely to be over their lifetimes?
It would come down to donor predictions, and different donors will generally have quite different predictions (similar to for-profit investing). I agree there is a further difference where donors will also value different outputs differently.
One other advantage of not quantizing the individual contributions of employees is that they can sum up to more than 100% - all twenty employees of an organisation may each believe that they are responsible for at least 10% of its success, which is mathematically inconsistent but may be a useful fiction (and in some sense it could be true—there may be threshold effects such that if any individual employee left the impact of the organisation would actually be 10% worse) - if impact equity is explicitly parceled out, everyone’s fractions will sum to 1.
I mostly consider this an advantage of quantifying :)
(I also think that impacts should sum to 1, not >1---in the sense that a project is worthwhile iff there is a way of allocating its impact that makes everyone happy, modulo the issue where you may need to separate impact into tranches for unaligned employees who value different parts of that impact.)
However, it might also lead to discontent if employees don’t consider the impact equity allocations to be fair (whether between different employees, between employees and founders, or between employees and investors).
It would come down to donor predictions, and different donors will generally have quite different predictions (similar to for-profit investing). I agree there is a further difference where donors will also value different outputs differently.
I mostly consider this an advantage of quantifying :)
(I also think that impacts should sum to 1, not >1---in the sense that a project is worthwhile iff there is a way of allocating its impact that makes everyone happy, modulo the issue where you may need to separate impact into tranches for unaligned employees who value different parts of that impact.)
This seems like a real downside.