My external drive got unplugged by accident while moving files from the internal SSD to the external drive, resulting in some files getting deleted on the SSD and not getting written on the external drive.
I tried to recover these files on the SSD by using Disk Drill, File Salvage, EaseUS Data Recovery and Techtool Pro 11, unfortunately without success.
(I ran the software immediately after discovering the issue, because I know that if I continued using the Macbook, there would be risk that the OS would overwrite my files.)
Can someone tell me: why is it so difficult to recover the files, and what else can I do to recover the data?
NOTES: (1) I already have the programs installed when I tried to do the recovery. That's because I previously had a similar problem and gave up on recovering the files after those recovery software did not work (2) my SSD is 256GB and after the transfer I had 13GB of space available. (3) I don't have a backup. I wish I did (;-( ;-()