NEW YORK -- In the Coen brothers' recent 1950s Hollywood satire, "Hail, Caesar!" Ralph Fiennes' ascot-wearing British director Laurence Laurentz is helming a stuffy drawing room drama full of tuxedoed men and ballroom-gowned women.

The movie, "Merrily We Dance," Laurentz declares is a "prestige picture." But it's clear that the Coens think so-called "prestige pictures" can be just as much a joke as any other type of movie. In its day, "Merrily We Dance" would have been destined for Oscars.

Lately, the narrow parameters of movies celebrated by the Academy Awards in the best picture category haven't been quite so funny. Self-serious prestige films have long found a ready seat at the Oscars, while films starring or directed by minorities have struggled to. There are many factors behind what's led to two straight years of all-white acting nominees, but one is the stifling limitation of what gets considered an "Oscar movie."

What frequently guides a movie toward a best picture nomination or a star toward an acting nod is a confluence of factors that frequently have only so much to do with quality. Influential is how a movie is released (a prominent festival rollout can pay big dividends), how much support a movie has from its distributor (the parties and advertisements that go into Oscar campaigns are expensive) and how willing the talent is to promote themselves.

"It's a racket," says Viggo Mortensen, who was nominated in 2008 for David Cronenberg's "Eastern Promises."

"The nomination process is essentially run by, dictated by money and public relations manoeuvring," Mortensen says. "And so that's why every year, there are only a handful of, in my opinion, deserving and enduring nominees of enduring quality."

This year's best picture nominees boast a handful of films from outside the film academy's traditional comfort zone, most notably George Miller's much-nominated post-apocalyptic chase film "Mad Max: Fury Road."

But many of the films that could have put a charge into this year's awards didn't fit the limited confines of Oscar bait. Ryan Coogler's "Creed," while it landed a nod for Sylvester Stallone's supporting performance, had the odds stacked against it. It's a seventh entry in a franchise and it wasn't much pushed by its studio, Warner Bros. Its humanistic heartbeat is perhaps -- like Coogler's previous "Fruitvale Station," also starring Michael B. Jordan -- outside the kind of films starring black actors that usually garner academy attention.

Few African American actors have ever won for a film by a black director. (A notable exception is Denzel Washington for Antoine Fuqua's "Training Day.") No black actress has ever won for a film helmed by an African American director.

The N.W.A biopic "Straight Outta Compton" -- which lacked a white protagonist or the historical sweep of "12 Years a Slave" -- also didn't fit the usual criteria. One academy member, the writer-director Rod Lurie, says he heard numerous academy voters dismiss even screening "Straight Outta Compton."

Taste plays a part, but the playing field is uneven. If it wasn't, Melissa McCarthy would have an armful of Oscars by now.

Like many genres, comedy is all but forgotten come awards season. This year, the trend reached a somewhat absurd endpoint when David O. Russell's sombre "Joy" and the nerdy space adventure "The Martian" sneaked into the comedy category at the Golden Globes.

It's one reason why Leonardo DiCaprio was passed over for his brilliantly outlandish performance in Martin Scorsese's "The Wolf of Wall Street," but is likely to win instead for crawling in mud and eating bison liver in "The Revenant." Only one of the 20 acting nominees this year -- Jennifer Jason Leigh in "The Hateful Eight"-- is straightforwardly comic. And even she takes a beating.

Films from outside English-speaking countries and documentaries have virtually no chance of gaining the same consideration for best picture as a historical epic or a lavish costume drama. If they did, the French-produced Turkish drama "Mustang," the tremendous debut by Deniz Gamze Erguven, might be vying alongside "Spotlight." Or Joshua Oppenheimer's documentary on Indonesian genocide, "The Look of Silence," might be a rival to "Bridge of Spies."

The Oscars are less about rewarding the best films than affirming Hollywood's sense of itself -- which is why exclusion so outrages. They are, the New Yorker's Richard Brody has written, "Hollywood's idealized self-portrait." That's one reason why Alejandro Inarritu's "Birdman" -- a film about a Hollywood star striving for artistic salvation outside of superhero films -- won best picture last year. It was a vote not just for "Birdman," but against Marvel domination.

Any award show is built on the consensus, and thus can drain away daring candidates, like Spike Lee's bristling "Chi-Raq," the iPhone-shot "Tangerine" or the fresh coming-of-age tale "Diary of a Teenage Girl."

Yet despite often rewarding mediocre films that fit a narrow standard, the Oscars matter. Outside of a Nobel or a Pulitzer, no award is more affixed to a person's legacy; "Oscar winner" is a tag that lasts past death.

But it's worth remembering: The lack of one didn't do much to dull the lustre of Alfred Hitchcock, Cary Grant, Barbara Stanwyck, Akira Kurosawa, Ingmar Bergman, Fred Astaire, Joseph Cotton or Marilyn Monroe.