If you are willing to trade your altcoins to earn profit, then it's not really important to put them on ledger. Meanwhile, if you want to hold for long-term investment (like for a year or more), it's better to store you coins on a wallet that you control the private keys to ensure that your coins are under your own security. This action is to prevent your funds from getting problem on Binance as we don't know what is going to happen tomorrow.