A movie that pleases 80% of the people that stumble upon it will do better than a movie that pleases just 20% of the people that stumble upon it. If you promote the first movie heavily, you end up with lots of profit. If you promote the second movie heavily, you end up with losses. Because marketing costs money. Fortunately, the Blair Witch Project was able to get a lot of cheap and undeserved marketing by spreading the rumor that it was a real documentary. El Mariachi didn't have any such luck so it had to rely on old-fashioned entertainment value. Hence the slight anomaly.You're right -- I misspoke on the 'higher score' part. But the point still stands -- MORE people watched 'Blair Witch' and rated it, FIVE TIMES more people. Assuming a direct correlation to audience, that would mean FIVE TIMES more people saw 'Blair Witch' than saw 'El Mariachi'. If that's what we're using as a measure of how 'good' a movie is, then 'Blair Witch' would have to be considered a far better movie than 'El Mariachi'.
What we're looking for is the subjective view of the majority of the target audience. If you show a movie to 100 random strangers in your target audience and 90 of them felt it was worth their time and money, then maybe it's a good movie. On the other hand, if 70% of them didn't enjoy it, then maybe it's not so good.Any kind of ratings like these are subjective at best. There's nothing to prevent the same person from voting multiple times. There's nothing to stop people who are financially or personally involved with the movie from voting, thus skewing the results. It's a crap shoot.
Your target audience is not the film festival crowd, but the man on the street, right? Then you can't say a movie is "good" just because a bunch of filmmakers in a certain film festival like it. Unless: you made the movie specifically for filmmakers, actors, etc. If the movie is for the filmmaking community, then you shouldn't expect Hollywood Studios to promote it because they need a much bigger audience. So, yes, it's all relative, but it's not that random.