Infrastructure Software

Dear guys,
When I tried to tar a folder to archive file,encounter error:"Error exit delayed from previous errors"
My tar command is:"tar -cvfz ar_src.tar.gz src" (src is folder)

but a interesting thing is, Once I changed command
from "tar -cvfz src.tar.gz src"
to "tar -czvf src.tar.gz src"
Then no error happen,why? I just changed option order,why no error happen?

Thanks
Pan