What Is the Recommended Practice for Key Reuse in Cryptocurrency?

The recommended practice is to avoid key reuse and generate a new key pair (and thus a new public address) for every transaction. This practice is called 'address rotation' or 'key hygiene.' Key reuse increases the risk of a successful preimage attack once the public key is revealed after the first transaction is spent.

Furthermore, it harms user privacy by linking multiple transactions to the same identity.