When you have made money from investing in altcoins, you may keep at your wallet or at exchange agent.This decision depends on you. If you want to hold it within several months to come, it will be better and safer to keep it at your wallet.you have full controll on it and at any time you can cash or transfer to another. While keeping at exchanger, will be more risky because you can not controll it directly. This is my short idea and advice.

Personal wallet is likely the most recommended but not that online wallet like myetherwallet but you should use the offline type like Nano Ledger in which a hardware wallet. If exchange and its wallet will be compromise, it will same with the personal online wallet in which booth can be compromise and can do an inside job scenarios.

Agree with you. You can store your money on exchange only if you are a trader. But for long-term investors it will be more safely to store their money on cold wallets.

If you want long-term investments, I can say that wallets are safer, but we use both. We prefer to exchange in order to shape the investments in the day

it is always best to keep them in a wallet and better than that a cold wallet which is not stored on you PC.

but it depends on your purpose for holding coins. i would suggest not to keep any coins on the exchange due to problems might occur as seen in the past.
so if you are day trading just pull them out at the end of the day. you might pay a bit more fees but your coins will be much safer.

It is better to keep funds in a cold wallet, or on an offline wallet, but only buy them from the manufacturer or an authorized representative, so as not to buy an offline wallet with a virus, etc.
In addition, the funds can be stored on the stock exchange for rapid trade in the case if the rates have changed dramatically in any direction (up or down). But this is more suitable for those who invest for a short term and focuses on courses and trading.
In addition, the advantage of storing funds on exchanges is the getting of new coins after the hardforks. But there a bad things of keeping the funds on the stock exchange too, for example, the possibility of hacking the exchange, the scam from the side of the exchange itself (not actual for the largest exchanges), long pending with deposits and withdrawals due to server loads or system failures.
And the best wallet, in our opinion, is the brain wallet. Use it wisely and then you will be fine, you just need constant updates of this wallet to the latest actual versions.

As it seems to me to work with amounts up to $ 10,000, you can use exchanges, but in this case I distributed the amount at least between three exchanges. After that, after increasing the deposit of the coin, which would deduce a lstrong coin to the wallet. Or, initially, to build a conservative portfolio and put everything on a wallet.

For me its better to keep your coins in wallet instead of exchange must be hacked any moment.In wallet you can have a private keys to make it secured and get increased by holding it.

If I myself save in some exchange, then in hold within a certain period. But there are some coins that are kept in the wallet. just a savings account, especially a POS wallet