Setting a high bar to new edits increases the cycle time to deal with edits in general. If we look at control theory for analogies, and take a feedback controller (say PID) you'll see that short cycle times often lead to quicker convergence and higher accuracy; even with very crude control; while long cycle times even with very fine control will lead to much less satisfactory results.

Analogously thus with a wiki. One of the things that make a wiki (hawaiian for "quick") work is that it (potentially) has very short feedback loops when editing.

One reason wikipedia is often slower than it can be is because very many people have the "slow but fine" intuition; but less people have/(or used to have) experience with the "coarse but fast correction" regime, and thus lack the intuition that comes with that.