You're equivalency to Bailey wanting to 'win more quarters' was 'to kick more goals from outside 50 towards the punt rd end of the MCG.' One is a simple metric to focus the mind of the players and the other is a deliberately outlandish and obscure metric to confuse posters.
Statistics in and of themselves are deficient, of course.
But this isn't by itself.
Bailey mentions quarters won to, as I said, simplify the game and focus the players. And he adds other measurements - like I50 discrepancy, consecutive goals against, and turnover-to-goal conversions are a few that Bailey harps on about.
These stats are needed to measure progress and I think some of this ire against 'quarters won' is about a push backl against statistics in the whole.
I think that having a go at Bailey for having a set of KPIs (even if you are criticising one in particular, because of a refusal to see the bigger 'statistic' picture) is misguided and unfair.