Yes
Actually, it says that the upload is done. But if you need to check the code that has been sent, you need to activate it.
Here you know that the upload has reached the end, you don't know if what's inside the ESP (or whatever) is really what you intended to send.
But most of the case it works well, I never activated the check step
Do you see a last message - "Hash of data verified." ? Do you want to say that's not enough to be sure that data uploaded correct?