"Objectivity" is the bane of my existence.
Mostly, it's because "objectivity" is one of those concepts that's impossible to define because the pure version of it doesn't exist. Every living person experiences the world through the filter of a near-infinite number of psychological and physical filters that color their perception in subtle or dramatic ways. When people seek (or claim to practice) "objective" journalism, for example, what's really being sought is generally "not openly biased" or "not agenda-driven" journalism. Like fairness, objectivity is a quality that everyone seems to want, but no one can really agree upon its definition.
Which makes it a colossal pain for those of us in the business of opinion and criticism.
The fact is, reaction to the creative arts is the least objective thing in existence. Our response is to something created solely/principally to stimulate the subjective senses. Everyone has their own unique take on what effect sights, sounds, smells, tastes, etc. have on them, and no two people will ever experience a book, film, game, whatever in exactly the same way.
Thusly, it's common to hear people devalue the work of critics on the basis that "everyone has different opinions," a factual statement used to imply that the critic's opinion is not really of any greater value than any random person's. For the most part, this is a simple misunderstanding of what a critic's job is. The point isn't that the critic's opinion is "right" while yours is "wrong," the point is that the critic is (ideally) more practiced/experienced with the subject at hand and thus their insights can help give you a greater understanding (or even reconsideration) of your own reactions. To put it another way, I don't critique movies to tell you how to spend your money, I critique movies to give you some of my thoughts to incorporate into your own decision making about how to spend your money.
More problematically, the impossible demand for "pure objectivity" in criticism often leads to people throwing around accusations of subjectivity or "bias" as a way of attacking a critic when their opinion doesn't match one's own. I'll cop to having been as guilty of this as anyone else in the past, having spent many a thread sniping at Hollywood Elsewhere's Jeff Wells, for example, for "bias" about this or that movie given his (open) contempt for geek culture. But, as I've come to better appreciate how this business looks from the professional side, I've also come to find better uses for a journalist's so-called bias than anger. When last year Wells (who gave me/us a nice unsolicited shout-out this week) took to Twitter to declare his resounding approval for Captain America: The First Avenger, it was to me a great indicator that the movie was probably pretty damn good if it could melt Wells' superhero-hating heart.
The problem is that, too often, the word "bias" (which just about everyone has, positively or negatively, in regards to just about anything) gets thrown around interchangeably with "unfair bias" or "dishonest bias." We all have personal preferences, and reading any more than a handful of any given critic's reviews usually reveals what said critic counts as their favorite or least-favorite genres, styles, artists, etc. Pre-internet, when criticism was generally discussed/debated primarily among the similarly devoted, this was an accepted facet of human (and, thus, journalistic) behavior. A critic would have to step incredibly far outside the boundaries of professionalism or public decorum for anyone to even think of throwing out accusations of dishonesty or ulterior agendas - and these were the days when a bad review actually could sink a movie! When such talk did come, it was often related to politics. Pauline Kael famously branded the original Dirty Harry movie "fascist" and angry fans widely attributed the opinion to her left-wing political views.
All of this, of course, has changed with the advent of the internet and an unending digital news cycle. Readers and viewers, saturated day in and day out in a media culture of infobite reviews consisting of little more than a plot description and star rating often react with confusion toward criticism of (attempted, at least) substance, as if unsure of how to approach critiques that come from an identifiable perspective or voice. So acclimated have we become to reviews intentionally stripped of personality so as to strike the reader as something they could see themselves saying that the hint of any bias (or even mere preference) seems exceptional ... and alien.