Extra pay for the 3 best posters is 1 way to go about it I suppose, but I feel like I am saying these guys were awesome and the rest of you were shit.
I look it as a challenge. I like to take everything positively, even a fail encourage me (the low feeling does not stay long). I investigate the reason of the fail, learn from the mistake(s) and next time for the same task I focus on avoiding the mistake(s) I did last time that failed me. If I consider myself is a good poster and feel I am better than any other of the campaign but if I constantly fail to achieve at least one bonus for several weeks than there must be something going wrong. It's either the manager is not doing his job properly or what I believed about myself (a good poster) is wrong. If I find my believe about my post quality was wrong then I can work in it and upgrade myself.
In short, when in a campaign I give additional incentive for post quality then I expect campaign members are taking it as an opportunity to challenge their own personal development.
If they're put into a tier, they already kinda have an idea where I think they are
Regarding tier. I already have one for myself from long time, private (anonymously like DaveF thought), only between the authorized person who works for R7 Promotions. I have several categories and under each category I have users.

If you did it 100% anonymously it might be better. Nobody knows who is making what. This way they can't / wont compare themselves to other posters.
Agreed. A good manager is more than opening a spreadsheet and counting the number of posts a user makes. Balancing act is the best way to describe it.
It's now a fact. Just look around and you will see everyone wants to be a manager these days. It's a race now. In a race, if you are always not upgrading your working strategy and skills then others will overtake you - simple. Only the bests will survive. It's good thing for the forum and the crypto ecosystem.
By the way, I am flattered :-P. Thanks to several of you.
To be honest, it's funny. People with limited skills will always blame others instead of upgrading their skills and imagination. We have manager who invented (claims himself) a few bbcode styling that took them dozens of hours of editing but forgot to patent it LOL. I guess, I should go and patent "
["hr"]" so that no one else use it or I should patent the idea of
"fixing line break in signature banners" for small screen lol.
Jokes aside, I don't think there are anything like I first, you are 2nd and he is the last. All of us managers who are top tier - have imaginations, skills, passions about campaign management - we already had done many things, experimented 10 times if not 100 times and constantly experimenting with new ideas.