SPOILERS BELOW FOR PEOPLE WHO WANT INCEPTION TO BE AMBIGUOUS ...

You can't unread this ...Early in the film we twice see how long the top spins in Cobb's real world. Eighteen seconds each time. In the last scene the top is still spinning after 44 seconds. Even if it were to fall during the end credits, there's no question this means Cobb is dreaming in the end.

But how could Cobb, the master dreamer, fail to notice this? There's only one possibility. Someone performed Inception on Cobb just as Cobb had done on Mal, Who did so, what idea did they implant, and why?

Prior to "waking up on the airplane", Cobb meets old Saito in what we may assume is limbo, There we see Saito reach for his gun presumably to shoot Cobb. We know from what Cobb told us on the first dream level that, heavily sedated as they are, guns can’t kick them out. They can only send them deeper.

And we don't know that the level with old Saito is limbo. We only know it's a dream at least one level deeper than the one where Cobb interacts with Mal and Ariadne. So when old Saito spins Cobb's totem and shoots Cobb, that can only send Cobb to limbo - where he's reunited with his children and where James says, in a house on a cliff, "we're building a house on a cliff".

Why? This is the only way Saito's phone call can wipe away Cobb's murder conviction. Even for someone as wealthy as Saito, doing so is impossible in the real world. So Saito's solution is to learn Cobb's Inception technique and use it on Cobb himself. While Saito doesn’t know the physical properties of Cobb's top — how long it spins – he implants in Cobb the idea that it's more important to be a young man and see his children than to check the totem.

Of course some may still say the ending is ambiguous even knowing that the top spins more than twice as long as it should. That just means Nolan has successfully implanted the idea in your head that the ending is ambiguous ... ;-)

I am genuinely trying to find a reason why you can watch this movie dozens of times??
I watched it like 15 times and still not planning to lay it off anytime soon lol.
It certainly isnt a perfect movie but, could it be the vibe that makes it so watchable?

I just watched Inception for the first time and wanted to share an interpretation that doesn't seem popular but makes a lot of sense to me.

Many ask why Saito is so much older than Cobb in limbo at the end. The usual explanation is that Cobb returned to level 1 and died in the van, and with three levels of time dilation, those few minutes for Cobb were years for Saito.

First off, the reason I don't like this explanation: how did Cobb get back to level 1? He clearly didn't catch the kick, because he would have just gone with Ariadne instead of convincing her to leave him. So how does he go from limbo to level 3, then to level 2, then to level 1, then back to limbo again?

I accept dying in limbo sends you back a level, since there's nowhere else to go, but that only gets him to level 3. If dying in level 3 gets him back to 2, and dying in 2 gets him back to 1, then dying in 1 wouldn't send him to limbo. It's inconsistent. If dying in any level sends you to limbo (as they say it does due to the sedative), then his path would have been limbo -> 3 -> limbo, and the time dilation from one level would mean only a few hours have passed.

So the first thing to realize is: Cobb stayed in limbo after Ariadne left.

He and Saito were both there for decades. In the opening and closing scenes, Cobb clearly has makeup on intended to make him look older. The reason Saito looks older is because (1) he was already older than Cobb in real life, and (2) Leo is too important of an actor to use a double.

Many think Cobb has just arrived in limbo when he meets Saito because he washes up on the beach. But that doesn't prove he is in the same spot as with Ariadne. Beaches can be hundreds of miles long. I think he's been swimming up and down that beach for years looking for Saito. He knew where to find Fischer because he knew Mal would have him, and he knew Mal would be in the world they built together. But he has no idea where Saito would end up, and limbo is implied to be huge.

The second thing to realize is: when they meet, Cobb and Saito have both forgotten they are dreaming. Notice in the opening scene, Cobb sits down to eat with Saito. If he knew he were on a mission, and had only been on it for a few minutes, why would he take the time to eat? Surely he would just get to the point.

No, I think after decades of wandering, Cobb has only a vague idea he is looking for Saito, and Saito has only a vague idea he is waiting for someone. Neither remember anything more. Cobb also realizes the totem is important and carries it, but he doesn't know what it does.

When they meet, the remind each other why they are there. Saito reminds Cobb by saying "a half-remembered dream" - notice the look of realization on Cobb's face when that happens. And Cobb reminds Saito by giving him the totem - Saito remembers to spin it.

The opening and closing scenes in limbo, thus, are two halves of the same scene. The order of events goes like this:

• After years of searching, Cobb finally finds Saito, who has been waiting for him. Neither remember why.

• Saito says "are you here to kill me? This belonged to someone I knew, someone in a half-remembered dream."

• Cobb suddenly recalls all of the events that brought him there, which are shown to the audience as the length of the movie.

• Saito repeats himself to Cobb, who has been staring into space for a while as he remembers. "Have you come to kill me? Someone in -"

• Cobb cuts Saito off and repeats the key phrase that reminded him - "someone in a half-remembered dream."

• Cobb convinces Saito, with the help of the spinning totem, of who he is and what they must do.

• They return to real life voluntarily by killing themselves, and their minds are saved.

To me, this scene is so much more powerful if Cobb has been in limbo for years, than if he had just gotten there. He made a huge sacrifice by staying there. He knew by going there alone, he would be lost for a long time and might not even make it back, but he did it to save Saito so their agreement could be honored and he could enter the US and see his kids.