I found this most helpful, and haven't seen him explain it this well before and didn't want it to get lost in the comments of node/3184 'Why's there fewer starred submissions these days?', so I politely quote it here.
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eihrul | 2011-10-15 01:40
The problem is that the mapping community is shooting itself in the foot. Quadropolis built mappers from the ground up, but now tries to operate at a level of sophistication that does not allow mappers to get feedback and grow. As has been said, new mappers are shoved away when they want community and feedback. Its standards are too high and simultaneously the wrong standards. I have a rough set of standards which I apply to maps for inclusion, which are really a balance of many aspects. If you only focus on one of the aspects, to the neglect of another one, the map is unlikely to get included. If you do a passable attempt at all of them, the map is likely to get included, even if it is not amazing. The bar is not amazing, the bar is balance. They are: