Macs need fewer (a lot fewer) updates/patches because of two things:
* The operating system is much more stable and secure than Windows. This, in part, comes from its simplicity.
*Such a small percentage of users have a Mac, that hackers don't devote much time to hacking it. The more people that use it (Windows), the more appealing it is as a target.

Thus, Macs still have security and misc. updates to download, but not to the extent of its Windows counterpart.

Hope this helps,
John