When you monitor a folder and a file is moved in this folder , it will not trigger

I monitor a folder for new files . These files are not copied there , but moved from other places .

The tool cannot understand these moved files . I tried the -r option , tried to make a second folder inside the folder I monitor , but it doesn't work .
If I copy files it's OK . Problem is that the tools that produce the files are moving them , not copying them.

