Always keep a little BTC in your account's wallet, even if it's .0001. In case you get phished or your account is otherwise compromised, it puts a 20 day delay on resetting the PIN if your balance isn't zero.
And if you're wondering "If my account balance is empty, why does it matter if my account gets compromised?" it's because these fuckheads will regularly check your account to see if you've added any money.
Or just use 2fa?