For me, the most annoying that come up is that when I sell my coins because when I'm selling my coins the transaction is so slow. So, I get nervous because I did not know if the transaction will be done succesfully or my money will be gone just in an instant. Another is that when I'm withdrawing my money, I did not get my passcode. And of course, I became so nervous because it quite too long for the transaction to be successfully done to give my passcode.