Linking to a search engine results page, such as a Google search results page, can produce unexpected results because a search engine results page (SERP) changes rapidly and may even be personalized, leading to nonidentical content for different people or across time.
In some cases, a link to a search engine results page may be more durable. For instance, a software project may have migrated from SourceForge to GitHub, making the old SourceForge link obsolete, whereas the SERP may show the “correct” link as the top result. Another example is a blog whose URL structure has changed; the old post URL might break but searching for the post title could yield the “correct” location at each point in time.
Tim Pope laments:
remember when the first google result for “commit message” used to be my blog post? how the mighty have fallen