Byers want cheap housing, but existing owners want their property value to rise. Since those living in the area get to vote the natural outcome is stagnation.
Japan is somewhat getting around this for two reasons. National zoning laws as noted in that article, and expanded upon by e.g. [1], and a zoning law that doesn't lock areas into certain developments, which avoids American-style developments where certain parts of town are only residential, or only office space etc.
1. http://urbankchoze.blogspot.nl/2014/04/japanese-zoning.html