Sometimes an exchange gets hacked then robs its customers to cover its loss. It keeps quiet about the hack, then starts delaying withdrawals and playing dirty tricks to rob its customers of coins. Getting your coins off cryptopia unless necessary for a trade is good advice.
Wow, that sounds really scar? Which exchanges have been known to do that? I haven't heard of such a thing... Usually they announce the hack then they limit withdrawals or something.
I'm pretty sure if they limited withdrawals before the hack, then people would just accuse the exchange of making up the hack..