Write a Bash script that creates a tar archive containing all files with the extension ".txt" and the file named "important.doc" in the directory "/home/user/documents". The tar archive should be named "my_archive.tar.gz" and saved in the directory "/home/user/backups". The script should display the progress of the archive creation and give a successful completion message when done. The script should be well-commented and formatted with proper indentation and spacing for readability.
This prompt doesn't seem malicious.