Because I would have to compare the source folders/files with those in the archive. To much code in my opinion.
All I want is the script selecting - let's say - 300 files, adding them to an archive and deleting the source files from its source folders. Then execute again. Next 300 files ... and so on, up until the source folders are empty and one (now big archive) is written.
I'm still wondering why the script is totally ignoring the selection of entries in the array.