Rotten Tomatoes film scores may not be accurate or reliable

8 September 2023

When it comes to quickly gauging whether a movie is worth watching (since life is too short for bad films), I glance at its Metascore, a rating of a film which is calculated by Metacritic. This score is based on, as their FAQ page explains, a weighted average of reviews from top critics and publications.

Take note of that definition, its significance will become apparent shortly. In terms of Metascores though, I find ratings of sixty-five or more usually means a feature is worth watching, and in most cases — though there are exceptions — the higher the score, the better film will be. Particularly films with scores going up into the eighties and nineties. And no doubt, it is every filmmaker’s dream to attain the perfect score of one hundred.

The other major player in the film rating business is Rotten Tomatoes. Despite probably being a more recognised brand than Metacritic, I’ve never really bothered much with the Rotten Tomatoes scores.

This stems partly from my initial misunderstanding of how Rotten Tomatoes worked, and the way I used to (mis)read a Rotten Tomatoes score, combined with the site’s name. To my then warped way of thinking, a score of, say, one hundred, suggested to me, until I eventually saw the error of my ways, that the title was one hundred percent rotten.

Yeah, right, whatever. But there’s always been something about the Rotten Tomatoes metric that has never quite felt right to me. For instance, only moments, it seemed, after being released in March 2022, Tom Gormican’s 2022 feature The Unbearable Weight of Massive Talent, had attained a Rotten Tomatoes score of one hundred. I remember thinking to myself, how could that be? Surely a film needed to be widely acclaimed, by numerous critics, and audiences — something that would take time — to earn such an accolade.

That early score of one hundred was likely an incongruity, based on a low number of positive reviews. Today the title has a slightly more modest Rotten Tomatoes score of eighty seven, while Metacritic rates it a sixty eight. I haven’t yet seen The Unbearable Weight of Massive Talent but a score of sixty eight sounds to me like it’s closer to the mark.

But the one hundred score garnered, albeit temporarily, by The Unbearable Weight of Massive Talent says a lot about the weaknesses of the Rotten Tomatoes scoring system, and in particular, how the ratings can be exploited, as Lane Brown and Luke Winkie, writing for Vulture, point out:

But despite Rotten Tomatoes’ reputed importance, it’s worth a reminder: Its math stinks. Scores are calculated by classifying each review as either positive or negative and then dividing the number of positives by the total. That’s the whole formula. Every review carries the same weight whether it runs in a major newspaper or a Substack with a dozen subscribers.

In the course of their investigation into Rotten Tomatoes, Brown and Winkie discovered evidence that some publicity companies were paying little known film critics, who were often bloggers, to write, for an incentive, a positive review of a film that had not been faring well at the hands of other critics. To reverse a poor Rotten Tomatoes score, it is, or was, merely a matter of publishing a sufficient number of positive reviews — regardless of the integrity of the publication — to offset the negative write-ups.

Trying to manipulate a Metascore in the same way, would be somewhat more difficult — though doubtless not wholly impossible — given Metacritic draws only on the reviews of established film critics and publications. This is an unfortunate outcome for film-goers, who felt they could rely on the accuracy of a film’s Rotten Tomatoes score, when deciding what to pay to see.

And to be clear, I have no problem with little known bloggers writing about film. I do so myself. But I think an assessment model more akin to Metacritic — where only the reviews of writers and publications with a certain reputation are considered — needs to be adopted by Rotten Tomatoes.