By default, without the "archive" switch, Gmail's filters add a label, thus making messages show under that label / IMAP folder, as well as staying in Inbox. This is essentially copying a message.
The archive switch makes filters add the new label and remove the Inbox label, this is like moving a message from one folder to another (and which is how message filters work in all other mail services I've seen).
I've been using this setup for a while now, and find it more convenient. YMMV.