Resistance is not necessarily futile

NY Times:

ISIS Hostages Endured Torture and Dashed Hopes

The death of James Foley in August at the hands of Islamic State jihadists in Syria was a very public end to a hidden ordeal shared with nearly two dozen other Westerners, who were routinely beaten, starved, subjected to waterboarding and sometimes traded for cash, his freed cellmates say.

During the Vietnam war The North Vietnamese were known for their torture routines, but there were some guys they could never break.  One Marine who was captured was such a difficult prisoner they finally released him to get rid of him.  It is the ones who are never compliant who are the least likely to be executed on video, because they will not cooperate with the propaganda show.  They are like the prisoners who would shoot the finger at the camera when they were used as props for propaganda.   Groups like ISIL might kill them anyway, but they would not be willing to show something that reveal a lack of dominance.

During the Iran hostage crisis the captors had the most trouble with the Marines.  The interpreters in Iran struggled to understand such phrases as "Go f*** yourself."  When there goal is propaganda such non compliance works and if their goal is just to kill you anyway it is not going to make much difference.