[shtylman]

The risk is not that your account will be debited, it is that you will go to your bank and claim the charge was not authorized by you after having moved the coins off their site. Now, maybe your bank account was compromised, and the attacker used your info to get coins. The bank will still refund you at the expense of coinbase. Remember, it isn't the "good" actors these actions are meant to protect against. A business like coinbase is a target 24/7 for many malicious individuals with access to lots and lots of compromised accounts.

[aryanet]

So this is good tip. I actually did transfer out my first bitcoing from Coinbase to Blockchain, so it makes sense if their algorithm doesn't like that. I just transferred that coin back in to see if it makes any difference. But frankly, it is impossible for new users to buy bitcoin on coinbase. I had used my daily limits just to find out about this problem.