Young Metro Don't trust Poloniex

Any exchange that lets you trade on margin is probably not above manipulating you with an insider advantage. Let's say some people high up the Poloniex management team discover a coin is about to be bigger than Dash or Monero but they don't want the stupid Joe Public running up the price before they can buy 1% or more of the entire network for themselves. How could Poloniex scam Joe Public out of his coins and secretly acquire their own? They could manipulate margin trades with fud, fake news or disabling of the wallet for "technical issues". They could leave a wallet in maintenance mode even though The devs have updated their wallet & Bittrex has been running smoothly. To keep Joe Public who only has a Polo account not Bittrex from buying at all. If a Polo wallet is not allowing withdrawals or deposits people will be less likely to buy that coin even on Bittrex because the Poloniex price will hold it down.

OR Poloniex could go full scam and keep a wallet like Vcash on their exchange but not allowing withdrawals or deposits from Joe Public while of-course anybody working with Poloniex's back end could still find a way to transfer cheap Vcash bought on Polo to Bittrex dump at profit then repeat the process until they have made fiat and Vcash while Joe Public thinks Vcash "isn't going anywhere" and misses out on the best crypto investment since ETH.