PANews reported on October 26 that Ethereum co-founder Vitalik Buterin published his latest article, "The Future Development of the Ethereum Protocol (Part 5): The Purge", which stated that one of the challenges facing Ethereum is that, by default, the expansion and complexity of any blockchain protocol will grow over time. This happens in two places: historical data and protocol features.
In order for Ethereum to be sustainable in the long term, there needs to be a strong counter-pressure to both of these trends, reducing complexity and bloat over time. But at the same time, one of the great properties of blockchain needs to be preserved: permanence. The key goals of The Purge are to reduce client storage requirements by reducing or eliminating the need for each node to store all history permanently, and perhaps even eventually declare; and to reduce protocol complexity by eliminating unneeded features.