The phrase "Not your keys, not your coin" underscores the importance of owning the private keys to your Bitcoin, emphasizing that without control over these keys, you do not fully own your BTC. This principle is particularly relevant for users of custodial wallets like Blink, where the platform holds the keys and, consequently, control over the funds. To ensure true ownership and security of your Bitcoin, it's crucial to withdraw your BTC from custodial exchanges and manage your own keys directly