What are the reasons for version management?

On March 10, 2005, the Mozilla Foundation announced that they would not release any further official versions of the suite beyond 1.7.x, since they are now focused on the standalone applications Firefox and Thunderbird. However, the foundation emphasized that they would still provide infrastructure for community members who wished to continue development. In effect, this means that the suite will still continue to be developed, but now by the SeaMonkey Council instead of the Mozilla Foundation. SeaMonkey 1.0 was released on January 30, 2006.