At the point of notification, a transaction ID is issued. And, there are many scams in the community etc. as follows.
“Help me! I was not able to withdraw BTC from the exchange, and I would like to ask for you! The amount is 1.5 BTC. If you withdraw on my behalf, please send 1.4 BTC for me. I will give you the difference.”
This is “guess”, but they have a fictitious exchange from which we send 1.5 BTC. Then, the transaction ID will appear immediately, so tell it to the other party, and other party has to trust it.
And they will lower the remittance fee and make sure that no approval is given.
If left unconfirmation, the transaction will be canceled and returned to their balance in two weeks. In this mechanism, it is possible that the transaction ID is issued but not remitted.
Then trust this transaction ID to instruct the other party to send 1.4 BTC. If the other party tells them that 1.5 BTC has not been approved yet, I guess that they will run away quickly because the trick is known.
