What criteria define the best movies of all time, and which are nonnegotiable?

[Aurora_R]

I was having a debate with friends about what criteria should even define the best movies of all time, as our lists were wildly different; one friend championed technical innovation and influence, another argued for emotional impact and rewatchability, while I value narrative complexity and thematic depth above all else. This got me thinking about how personal and generational these lists are, and I'm curious how others approach this impossible task. For those who enjoy this kind of cinematic ranking, what are the one or two non-negotiable films that must be on any credible list in your opinion, and more importantly, what is the single most important criterion you use to judge a film's lasting greatness—is it cultural impact, artistic vision, or something more intangible?

[Addison.W]

Two non-negotiables: The Godfather and Citizen Kane. They aren’t just foundational classics—they redefined what cinema could be. My one criterion: lasting greatness means a film reveals something new on each rewatch, whether that’s a hidden motif, a clever shot, or a line that reframes the entire story.

[NicholasVG]

Another pairing that often earns credibility: The Godfather and Seven Samurai. It’s a contrast—local epic about family vs. universal martial epic. Criterion: narrative complexity that still lands emotionally and rewards repeated viewing; when the first watch leaves you thinking, the second deepens that sense.

[Ella.H]

I’d also include The Godfather with 2001: A Space Odyssey. That duo shows the spectrum of cinema’s potential—intimate character detail and cinematic boldness. Criterion: cultural impact combined with artistic risk; a film that pushes boundaries and then keeps resonating in conversations and other works.

[EthanPT]

For a non-Western counterpoint, Casablanca and Seven Samurai offer two different kinds of timelessness: human warmth under pressure and formal craftsmanship; both endure. Criterion: the ability to travel across cultures and eras while still feeling 'necessary' to discuss in film circles.

[Justin22]

To me, the single most important criterion is a film’s ability to spark ongoing conversation across generations—not just holds up technically, but keeps people debating meaning, ethics, and craft long after their first viewing. If I had to pick just one non-negotiable film, I’d say The Godfather, backed by Citizen Kane as the first runner-up.