It's all Darwin, survival of the fittest. Over time, the best modules are most likely to survive. Programmers will communicate and mention those modules they find most useful. When others need a module to do a specific task they are most likely to choose those they remember having heard the most positive things about. Evolution in action.

I have used the word most more than once(by design, really!). Programmers are people and people can be fickle and illogical at times. Sometimes a module will be popular though there may be better modules doing the same work. A situation somewhat like Betamax versus VHS. A rating system does little good in such cases because ratings in the final analysis are a measure of popularity. Does such popularity make a module fit? No, but it does make it a survivor.

The point I am laborously trying to make is that pollution can be hard to get rid of. I believe the best solution is to let the module users select the modules that are best. Not a perfect system but none is and better than selection by committee (or, god help us, management).

xenchu