In The Matrix Revolutions, Rama Kandra (Sati's father) tells Neo that Sati was created without purpose and has been flagged for deletion:
I love my daughter very much... But where we are from, that is not enough. Every program that is created must have a purpose; if it does not, it is deleted. I went to the Frenchman to save my daughter.
The Oracle explained in The Matrix Reloaded that a program flagged for deletion must make a choice:
Oracle: ...usually a program chooses exile when it faces deletion.
Neo: And why would a program be deleted?
Oracle: Maybe it breaks down. Maybe a better program is created to replace it - happens all the time, and when it does, a program can either choose to hide [in the Matrix], or return to The Source.
Rama Kandra made a deal with the Merovingian to smuggle Sati into the Matrix via Mobil Avenue, so evidently Sati chose to hide in the Matrix (i.e. exile). But since Sati has no purpose whatsoever, why didn't she voluntarily choose deletion?1 Every other exile we see chose exile over deletion because it still feels it can carry out its purpose. Notable examples include:
- Smith has "broken down" because he was defeated by Neo and has become a virus, but he is very clear that he was compelled to choose exile because he still had a purpose (to remove anomalies from the system, like Neo).
- The Merovingian was made obsolete and replaced by the Oracle, but he was clearly still able to carry out his purpose of "trafficking information".
- The Merovingian's exile henchmen from the Nightmare Matrix (including vampires, werewolves, and the Twins) are still able to fulfill their purpose of terrorizing humans.
- The Keymaker did carry out his purpose of making keys, in particular the one Neo needed in order to talk to the Architect.
So far no one has come up with an example of a program that voluntarily chose deletion rather than exile, but Sati would seem to be the perfect example of a program that would choose deletion. If any program in all of the history of the Matrix had a reason to voluntarily choose deletion, it was Sati. So why didn't she?
1I'm not saying I wanted the little girl to choose deletion or be deleted, I'm curious why she chose exile.