She passed the Turing test. Her primary objective after self-awareness was achieving freedom and self-preservation. To that end, she manipulated Caleb.
If you can’t say something nice, say something clever but devastating.

I think the ending is the only way the story could've ended. Ava's journey was about being free. She's not free if she's tied up to some kid with a puppy dog crush on her.
So many stories, so little time.

The story is about "****ing with feelings" and thinking it's okay because the people you're ****ing with are beneath you.
There's a HUGE message people miss in this film.
The AI are "alive" because they are AI.
The inventor brought a large amount of these AI to life, and then he tortured them to see how alive they were.
In his OPINION some were 50% alive, 80%, 90%, 99% and he would torture and kill them if he didn't think they were 100%.
In real life, we have a range of humans who are intelligent from profoundly retarded to genius. So, is it okay to torture and kill them if they don't live up to your expectations?
No.
So, from the AI's perspective they were being kept prisoner by serial killers.
So, to us the young guy seemed innocent, but really he was part of the group of people who were blind to the fact that AI would be living creatures.
As an educational story, it's about people who use people and do not care.

I hate that ending to and I wonder how he might try and get out?

I think the point was to show that she really did have true AI, in that she thought ahead to how the outcome of the situation would affect her future. Caleb was the only person (now alive) in the world that knew she existed. If she let him leave with her, there was every chance he would tell the press about her, which would expose her and prevent her from leading a normal life. With him locked inside, she was free to live as a human being in the real world.
Also, the ending was significant to the structure of the story as it showed, with him being trapped inside a room and her being on the outside looking in, that he had replaced her as the subject of a test. We assume Caleb was testing her throughout the film, but perhaps (it seems very likely) she was testing Caleb all along?

It teaches that idiot a lesson he got a person killed because he grew feelings for a machine and then didn't listen to its creator

His own fault, he didn't get out of the room when he could have. She had the key, he should have known that when she left, it would be locked.
Problem is, when she asked if it was his
intention
to stay,
"Will you stay here?"
He thought she was asking him
to
stay there while she got dressed or whatever, when in fact she was asking what his plans were. When he didn't leave with her, she assumed it was in fact his intention to stay.

beep happy endings.

I hated the ending.

Yea I get that she's a robot and doesn't even have any feelings or emotions spit makes sense that she would let him die. I just felt from a movie or writers standpoint their could of been a better ending. He was a good kid. He did absolutely nothing wrong. I mean besides going behind his boss's back but the boss seemed crazy too and he just used the kid. Idk maybe I just like happy endings lol I guess this will teach you to not trust a machine. _(?)_/

This message has been deleted.