Blockchain, which has a decentralized management structure, is a technology that challenges conventional wisdom about the availability and durability of an unstable structure, because the network system is managed by volunteers, as opposed to cloud- and network-service providers that leverage centralized management structures. The most popular services based on blockchain (e.g., Bitcoin and Ethereum) have structures that make it challenging to close or discontinue services unless all users agree, no matter if they are honest or malicious. Remarkably, this structure shows stable availability and durability, even now. Considering that unpopular services are eventually terminated, there are more than 2,000 service projects forked from Bitcoin and Ethereum, and it is not realistic to expect all of them to operate in the same manner. When users abandon services like these because of low interest, the blockchain, which depends on volunteers to maintain the system, is affected by reduced availability and durability until it is finally closed. However, unlike centralized management organizations, for service closings, both the indicator and closing mechanism are unclear, because management depends on user dynamism. Therefore, we investigate the mechanism of public blockchain closing by focusing on three decentralized roles of blockchain users. Then, we discuss the closing implication of blockchain-based services using the empirical analysis of 200 different systems.