It's quite unusual that even at this day and age, with a lot of techniques and new practice on safeguarding a platform, hackers are still able to get through even with the robust of security systems. I wonder how tight their security are and what their system admins do for the hackers to still find a vulnerability on the platform. Also, this stresses the age-old question of whether to keep your funds in an exchange or not, and the answer is laid right before our eyes every time a theft occurs.
It is not really that unusual, there is nothing that is hacker proof, with enough time and resources a group of hackers can figure out how to enter a system, but the problem for them will be the costs, when it comes to a centralized exchange it does not matter how much time or money it took the hackers to get access to the funds of the clients of that exchange, it was worth it, but if you are the only one holding your coins and the amount of coins you have is low and your security tight then it is not worth for a hacker to try anything against you.