Great post @zneeke!
Many crypto beginners run into these little catches that can end up costing a lot of money.
One thing I might want to add, those withdrawals (in contrast to trades) are "on-chain" transactions, so apart from the exchanges taking their fee for withdrawals, this also includes network fees.
For that matter one should always check the state of the network (almost all major cryptos have solid block-explorer sites that offer such infos) and IF those fees are adequate or on-chain transactions even feasible.
Especially with bitcoin this has recently been a major problem due to the huge backlog of unconfirmed transactions and the accordingly higher fees.
Thanks for that info @fraenk. I was so lost in the article that I forgot to mention that. :)
haha... yeah I know that feeling :P