What does 80% of 80% mean?

Because the people working on tasks in my plan can only work 80% of their time on a task I have set each person’s units % to 80 and their efficiency set at 100%.  What I see now in OP is beside each person assigned to a task “{80% of 80%}”.  What does that mean?  Why isn’t that {100% of 80%} where the first % is efficiency and the second % is units?
Or y’all could show {80 units at 100%} meaning 80 units at 100% efficiency.

I just realized that the {80% of 80%} indicates 100% of 80% units (I think). Still, y’all need to rethink how to display the unit/efficiency for resources as the current indication is not intuitive.