While sorting my images with
exiftool "-directory<EXIF:DateTimeOriginal" -d %Y%m%d -ext jpg .
for some of .JPGs exiftool reported an error
Warning: [minor] Error reading PreviewImage from file - ./P5030553.JPG
What does it mean, and is this something one should be worried about with regards to potential future problems and with regards to integrity of images?
Almost all images in question came from a smartphone camera and Olympus camera, with no problems during transfer or alike.