One of the reasons it’s important to inspect attics is to look for signs of water intrusion.  Here you can clearly see water intrusion from a roof leak in the attic.  Nothing was (yet) presenting at the interior finishes within the home, but it’s a matter of time before the roof leak worsens and leads to roof structural damage and leaks to the interior.  I always advise my inspection clients to have someone take a peek into their attic and crawl space on an annual basis looking for signs of water intrusion; if you find it sooner than later, the repairs are much less expensive.  Water is the enemy to homes in the Pacific Northwest!  This was discovered at a recent home inspection in Friday Harbor on San Juan Island.