Cancelled cut and paste, what happens?

When you cut and paste the data, the data transfer proceeds one file by one from the location of transfer to the other location. Until the file transfer is completed, the files are not deleted from the original location(from where the files were cut). If by chance the transfer is interrupted the files which have not transferred yet will remain in the original location and you can again proceed with your transfer.

There is a very small chance of losing data if the transfer is interrupted by a power failure or a system hang. In my case I've never lost data when cutting and pasting, no matter the size.

No file should be lost. Information that was copied will remain copied, and information that was not copied will remain where it was.