It needs liquidity. Nice platform with low liquidity is like building an arcade with no gamers showing up. Or worse to build a new console to replace "centralized" arcades yet no one buys the console. Or worse they buy the console but don't know you can play games over the Internet so no need to go to the arcade.
People who are not part of geek culture and who do not like to test new technology will have to lose their money to centralized exchanges or find the limits of what they already do before they will look to something new. Bitshares is new but most people think why not just keep using Poloniex? It is only when you can't find that new DAO token on Poloniex or you can't do a certain kind of financial function anywhere else will people have to switch for the most rational reason of profit seeking.