The most useful contributors are busy contributing. Hurrying them to improve an article (or risk deletion) results in a stressful and counterproductive environment. We should allow editors to work at their own rate; this is a work in progress -- lets not fool ourselves into thinking that this will change anytime soon.
If somebody, who adds a poorly-written article to VfD; instead, took 15 minutes to research and improve...the Wikipedia would greatly benefit.