When you wrap and executable installer in an MSI package, the executable is compressed and stored inside the MSI. At the time of installation, the wrapped file is unpacked to a temporary directory and run from there.
It is also possible to include other files with the MSI package. The MSI Wrapper can optionally include all the files and folders in the same directory as the executable. If this option is used, all the files are unpacked to the temporary location.
This feature is useful if your wrapped installer requires other files during the installation. You can also use it to include additional resources such as registry files or batch files, which should be run during the installation.
Please note that the temporary directory where the files and folders are unpacked to is removed when the installation is done. Therefore, any files that you want to keep should be copied to another location.