Coincheck was one of the few crypto exchanges that used hot wallets not cold wallets, which are not secure
No excuses or explanations were given so far in this case, but it’s under current investigation by Japanese Financial Services Authorities. This is by far the largest theft in the history of the world. Other suspicious activity included a massive transfer from the Coincheck Ripple wallet equating to roughly $110 million USD. No word yet as to whether the transfer and the massive hack are related. There has been a sustained drop in the Japanese crypto market. This may be a death blow to the regions crypto exchanges, but the hack has created a bit of bounce for the US dip as investors anticipate the stolen currency will be converted to other coins and tokens.