[_yy]

Incident response. When one of your admin accounts is compromised, you'd want to know what the attacker executed.

[ultramancool]

Yes you would - but why just SSH? Wouldn't auditd execve syscall logs sent to a logstash server be better? It'd handle compromises other than SSH too.

[_yy]

Yes - though there's more to a SSH session than executing commands (interacting with interactive editors, port forwarding, etc.)