Google search is infinitely ubiquitous for its usability, efficiency, and... well, it's lack of accuracy. But I have found many problems with it.
The single problem that screams most prominently is Google's own ad service in which invariably ads will clog up any hope you had at finding any information regarding your query other than its Wikipedia page, and If that's what you want, then why not set your homepage to "Wikipedia.org"?! Google seems to truly have stooped rather low in order to garner support from the world of least common denominators out there. Which brings me to my second grievance; AutoComplete. AutoComplete is likely the single feature in technology that has made me lose faith in humanity. It is the most embarrassing display of the average human's lack of intelligence by some of the extremely lame-brained that have been voiced, and has convinced me of how sexually-obsessed and entertainment-hungry society is. It is a shame, but what can you expect from the world's least common denominators and their tendencies to be attracted to violent or otherwise inappropriate forms of media.