When setting up an NXT account, it is recommended to send a transaction out in order to secure your account. I don't quite understand why it's needed. I know that if you don't send one out, your account is only 64-bit encrypted and when you send it out, it becomes 256-bit encrypted. I don't see how that makes a difference as you can still brute-force it regardless given an amount of time.
Why is it necessary to encrypt it when sending an outgoing transaction compared to just receiving one?