[tor-relays] No obfs3 traffic at all on bridge

Hello, my obfs3 bridge has now been up for > 20 days. I have iptables rules in place to count packets. To date, I have not seen a single packet to either the obfs3 or the scramblesuit port. Both are working though, I just tried them with the Tor Browser. Is this a good sign (i.e. the bridge is still in reserve) or a bad sign (something's wrong)? Thanks for any help! Marco