How is the disk verification feature supposed to work when writing an iso to a USB?

I recently wrote a Trisquel 12 iso to a USB stick following the LiveUSB guide [1], using the "Trisquel (Graphical)" method, and at the end when it says "Installation Complete", there was a button to the left of "Quit" that said something like "verify disk" or "check disk", and I decided to press that. It prompted for my user password again (the first prompt was when writing the iso), and then after I put my password the window disappeared with no indication that anything was still happening. The USB device was already ejected since the disk creator works on the disk correctly and doesn't mount the partitions to the operating system, so I took the USB stick out after a minute or so.

What is supposed to happen when I try to verify the disk? Shouldn't there be a progress bar or indication that something is happening? How can I know when it is finished?

The USB stick seems to work fine regardless.

[1] https://trisquel.info/en/wiki/how-create-liveusb