The Barzan wormhole destabilizes
A subspace axis is a central component of the stability of a wormhole.
In 2373, two Ferengi, Arridor and Kol, emitted a graviton pulse near the Delta Quadrant terminus of the Barzan wormhole, an act which had the effect of knocking the wormhole off of its subspace axis, causing both ends to shift positions randomly. (VOY: "False Profits")