What Happens if I Run a Photo Fixer Twice?
Running the same job again on the same folder, and why it should be harmless.
A well-behaved tool is idempotent, which means running it a second time changes nothing. The dates are already correct, the files are already named and foldered, so there is nothing left to do.
The risk with rename-and-move tools is a second run treating already-organised files as new input and nesting folders inside folders, or appending the date twice. Always test on a copy the first time with any tool.
Takeout JSON Metadata Fixer keeps a small index of what it has already organised, so a repeat run recognises its own work and leaves it alone. It also previews what will change before writing anything.