Performance Metrics for employees in early stage startups

What is a good example of a Performance metrics to be applied for an early stage startup? I find it very difficult to know how people in the team contribute; thus it's difficult to distribute equities to cofounders or grant equities to early employees.

The same questions for a medium-size company?

In our start-up, none of the early team or co-founders came from a background of having started any other business or worked in a large business. So we basically just learnt this as we went.

The first thing we looked at is bottom-line and who contributes to it. We struggled to justify the positions of those who were only working on long-term goals and did nothing for our revenue in the short term. When things got tough and we almost ran out of our runway, we looked at the team and had to let go of those who made little or no contribution to sales. Since then whenever we hire someone, we always align their workload to always include an element of "what is important to us now". So CONTRIBUTION TO BOTTOM-LINE was our first metric.