What gets rewarded gets done. Hence the assorted debates about what is counted or not in Warhammer public quests. How are things like taunting, holding aggro, taking damage, buffing, healing, and dealing damage credited? You want to optimize your Skinner box experience.
What gets observed also tends to get done. 10,000 years of evolution is not much, and your primitive brain still wants to make sure that you look good in public, to improve your reproductive odds and reduce the chance of being clubbed. (FYI, despite your brain’s hardwiring on alpha male status, having the best paladin on the server is unlikely to get you laid.) Monitoring increases other-directed behavior, which you know because of how Internet anonymity affects people. If your primitive brain recognizes that others can see you, it will act accordingly, just as it recognizes when it is easy to freeload.
Warhammer scenarios track a few things, reward a few things, and do not show exact connections between them and other factors. You get experience and renown. The scoreboard (at the end or any time during) shows damage dealt, healing dealt, deaths, and kills. It does not show damage received, damage prevented, resurrections, damage increases due to buffs, flag captures, or whether you were strategically useful at all. That last one is hard to measure consistently, but you might imagine how these other measures (or lack thereof) affect behavior. Healers will compete for their scoreboard, as will damage dealers. No one is rewarded for guarding the flag, unless the enemy is throwing itself against yours, in which case the best rewards are for turtling rather than risking an attack on the enemy flag. I get a better reward for healing you than bubbling you. Sacrificing yourself for the team means that you miss out while you wait to rez. And so on. And no one will know that you did anything that does not appear on the scoreboards.
You can be the greatest fielder in baseball, and it will not show up in your statistics. The pitcher gets credit for that. I hope someone is taking those Sabernomics into account.