Delegated Byzantine Fault Tolerance (DBFT)

• Instead of everyone getting to participate in the validating process — which can be incredibly limiting in terms of transaction speed — those who hold for instance NEO tokens (which uses dBFT) can vote for delegates. These delegates (called bookkeepers) maintain the network for everyone. Thus, NEO can run faster, more efficiently, and with quicker and more finite decisions.
• Remember too that these bookkeepers will have their digital identity known, making NEO much more compliant with national regulations. Which you can view as a good or a bad aspect.
• The disadvantage with this system is a lack of decentralization. In its purest sense, instead of thousands of validators being scattered all across the world, governance is concentrated in a few dozen validators. The majority of these nodes are currently operated by the NEO team. However, as of Quarter 1, 2018, NEO will hold less than 2/3 and will continue to hold fewer as time progresses. Regardless, NEO will never be as decentralised as other pure PoS platforms.