Stories change
For example, I recently re-read EB White's "Charlotte's Web" for the first time since I was a child. I remember loving the relationship between Wilbur and Charlotte, and Charlotte influenced my feminine ideal: intelligent, worldly, caring.

Now that I read it again, Charlotte seems different. She's distant, for one thing. I don't think she touches Wilbur in the entire book, though granted she's tiny relative to him. She's bossy, when she tells Wilbur to run around, and doesn't involve him in her planning. She also rambles about things that are of no interest to Wilbur.

I also wonder why people are so impressed with the pig instead of the spider, as Mrs. Zuckerman suggests. I think this has something to do with White's commenting on advertising.

In "The Empire Strikes Back", I always thought that, at the end of the confrontation with Darth Vader, Luke is so stunned by the revelation of his parentage and the loss of his right hand that he just passes out and falls off the platform. It's only by luck and/or the Force that he gets sucked into the vent and doesn't fall all the way.

When I saw the scene again recently, I had a completely different take. Luke briefly glances down into the chasm, then back at Vader, then allows himself to fall. Another shot shows Luke in almost a skydiving position on his way to the circular vent.

An apparently minor change, but with huge ramifications. The basic idea is the same, that Luke would rather die than join the dark side. However, instead of Luke giving up and being willing to die, only to be saved by an external force, Luke escapes Vader by grasping at a thin but definite hope for survival.

Anothe example is Moore and Gibbons' "Watchmen". There are so many intricate details in the story that it is full of things you notice on re-readings. On the first few pages, I noticed that when Daniel is walking towards his kitchen, his hands are in fists and his shoulders are squared. He may not be Nite Owl anymore, but he can still handle what he thinks is a random prowler.

Likewise, Dr. Manhattan doesn't leave Earth because he's worried that he's emitting harmful radiation, or that he isn't human anymore. He leaves because Ozymandias' machinations make him realize that he's still human enough to panic, to make rash acts, and for a being with nearly unlimited power, that's unacceptable. The whole business with him and Laurie on Mars is him trying to make her break up with him, so she feels she has some control.

So, stories change in the telling and the reading and the remembering. They're all acts of interpretation.