Mark Cuban once picked Ethereum (CRYPTO: ETH) as the cryptocurrency offering the highest upside potential. Today, the billionaire investor says he is deeply disappointed by how it has turned out.

Cuban’s Frustration With Ethereum

In an Aug. 21 podcast with tech journalist Kara Swisher, Cuban weighed in on cryptocurrencies and a once-bullish narrative that didn’t unfold as he had anticipated.

Cuban acknowledged that he was “excited” by Ethereum’s smart contract functionality and believed it could have been put to better use in building new kinds of applications that supply data to other systems.

Smart contracts are self-executing computer programs stored on a blockchain and run when preset conditions are met. They have been widely…