Unfreezing a driver?

acdds

With the current discussion whether or not vintage polks will last forever, is there any way to repair damaged drivers? Specifically, midrange woofers that are seized. I recently replaced one and have been playing around with the old one. I got the magnet off the back (the glue had released). Without the magnet, everything moves freely again. I have no idea about the construction of drivers, so can someone state the theory behind seized drivers?

Thanks!