it isn't a matter of total time this takes, it is a matter of de-focusing and doing a bunch of small refinements ahead of major features - that can set you back for a long long time. there is a neverending list of small and minor improvements that can be made to ANY website. but it is the major features that make the site good. it's the old 80/20 rule - the first 80% matters the most, and doing the last 20% takes just as long as the first 80%, but doesn't give you the same return on investment of time :)