The text explores the concept of self-custody in cryptocurrency, emphasizing its importance to crypto purists who advocate for direct control over crypto assets rather than relying on centralized exchanges. Self-custody, however, presents challenges such as the risk of losing cryptographic keys, which can result in irretrievable losses. To address this, the text introduces the notion of social recovery, where individuals can enlist friends, family, or even institutions to help recover lost keys, a concept termed "fourth-factor authentication." The text highlights the potential role of institutions using systems such as DECO, which allows users to authenticate in a privacy-preserving manner without explicit support from the institutions. By incorporating both social and institutional support, the text suggests that self-custody could become more accessible and secure, ensuring the viability of cryptocurrency as a technology and social movement.