A) allocation (send people to what they do best)
B) incentives (make people try hard).
I think meritocracy helps with both of these, but a lot less than we tend to think.
en.wikipedia.org/wiki/Kim_Ung-y…
In the short term, negative motivation -- "work hard or you'll suck and fail" -- can be very effective...
Sprinting isn't totally unlike distance running, but the two are different enough that we shouldn't assume that doing well at the former means one will do well at the latter.
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