Coins should always be considered in a safe storage, there are lot of wallets and platform that could be used to hold coins, both of this has good side and bad. Where will you choose to store or hold your coins, in a close source wallet (exchanges) or an open source wallet like electrum and Hodler wallet?
I believe that people won't make exchanges an option now after another known exchanges has been hacked. To my fellow traders, I know you have read or watched a topic about the best wallets for crypto and 99% of them does not recommend to put it on exchanges and they want you to use hardware wallets.
Yes, many exchanges are hacked 2017 middle and hole 2018, But if he uses the hardware wallet, he will get a lot of good security which is almost impossible to hack, more so that it can be said that there are many trusted exchanges(Ex.Bittrex,Binance) whose security is very hard to use them.