Dash's failure at trustless decentralization is the test case that formed my understanding of why trustless decentralization is necessary for any cryptocurrency to succeed at being disruptive. Dash's failure is that it built a centralizing flaw that aggregates coins to those who run nodes and layering power functions (votes, fees, privacy, etc...) onto these nodes.

Dash's nodes have two major weaknesses in design: first, they are pay based, or paynodes, which means that they can be bought and sold. The second flaw in design is that they collect fees, which means node holders collect money that in turn can be used to buy more nodes that in turn can collect more fees, and so on and so forth. Where this especially becomes troubling is that dash's launch produced 2 million coins in 2 days and this initial distribution cannot be verified to be fairly distributed, which means the resources to buy 2000 nodes (more than half of current existing at this writing) were made available to a few lucky guys who happened to be mining at that right moment--considering this is 30% of current distribution and given that they could have bought 2000 or more masternodes since that scheme was introduced, the number of masternodes these initial miners could have may be considerably more than 30%, and considering that this control can aggregate over time, it illustrates why these systems need to be trustlessly verified.

I apologize for all the numbers just thrown at you, but lets make it simpler, since the masternode system collects the revenue that determines its degree of centralization, and that centralization can't be verified to any statistical certainty, we should assume that it is increasingly trending towards a traditional oligarchy or monarchy, where one or a few have undue power over the entire system--how it behaves, the distribution and security of its benefits.