why do cryptoexchanges do this?

[Cjsantos01]

Hello guys I am very very new to this crypto world and I have a question that I still can’t get an answer for so please help me out here.
Why do some exchanges allow to deposit xrp (for example) but do not let you withdraw it?
I mean if I want xrp to hold it why the hell don’t they allow me to withdraw it to my wallet and needs to be in their site? It’s not only xrp there many coins in many exchanges like this
Thank you

And happy new year to you all

Ps: I already asked this question to many exchanges and no replies so far

[john111john]

I would think this is because you are using an exchange where you do not actually own the coins, you are purely opening a position as to how well they are going to do.

[Midoucha]

On which exchange are experimenting that?  Could you tell me please. Ty

[Cjsantos01]

hello here are the ones that are in the top ten of volume in coinmarketcap but do this. all of them accept deposits in the following coins but will not let withdraw them,. bithumb: EOS BTG    huobi: NEO ICX GAS NAS binance does this aswell but they explain such as high transactions volume so withdraw is temporarily suspended. there are many other in the top 20 that do this but it takes a lot of time to check them all out again

[Cjsantos01]

I would think this is because you are using an exchange where you do not actually own the coins, you are purely opening a position as to how well they are going to do.

it could be that but think with me if they are only opening positions an not trading really then there is no logic in accepting deposits on EOS.
an example BTC/EOS if they are just opening positions and not trading i would deposit btc do a trade an when i take profit from that i will take profit in btc not in eos and the opposite is aslo true if they are opening positions just like the forex market if i deposit eos and trade the profit will be in eos because this is not an actual trade. regarding that it is useless to accept deposits in eos because if you want to especulate in BTC/EOS you do that with btc
the same way in forex when you deposit dollars then you open a trade in EUR/USD you will not get eur for that trade

[darkangel11]

If they are suspending withdrawals it means they don't have enough of those coins in their wallets. It's really easy to understand if you think about it.
Let's assume there's 100 BTC on an exchange when they're opening and 1000 coins of a certain altcoin X, which at this time is worth the same as 100BTC.
Someone deposits 10 BTC, buys 100 altcoins and withdraws. This repeats 10 times and suddenly they are out of X. They need someone to either come and deposit it or they have to exchange themselves. Trading is still possible because it takes place in the API and the exchange is still solvent. They have assets in other coins (200BTC) but not the one that is experiencing a rise in demand.