One of Bitcoin’s long-time supporters and developers is walking away from the digital currency. His reason: the Bitcoin experiment has failed.

Mike Hearn is a devoted Bitcoin enthusiast who quit his job at Google to work on the cryptocurrency’s technology full-time. But last week, Hearn wrote a lengthy blog post on Medium, explaining why he has decided to turn his back on it.

“The fundamentals are broken, and whatever happens to the price in the short term, the long-term trend should probably be downwards,” he said. “I will no longer be taking part in Bitcoin development and have sold all my coins.”

In his post, Hearn offered a detailed explanation of why he has lost faith in Bitcoin and its community, which actually boils down to one thing—internal politics. The developer admitted the decentralized blockchain technology has some shortcomings that have caused problems for users, which is further aggravated by infighting within the community.