If I were to venture a suggestion: statistical significance may be relevant to your valuation of high-average high-number posters like Yvain, MichaelGR, and myself over higher-average low-number posters like michaelkeenan. If poorly-selected quotes nevertheless have a small but significant probability of being highly ranked (but a simultaneous large probability of being low-ranked) and most quoters select poorly, someone with only one high-rated quote is not much likelier to be a good selector of quotes than not. In contrast, someone with many quotes, most of which are highly regarded, could be expected to be unusually discerning, as the probability of this result by chance is low.