In season 4 episode 10 of The Expanse Ashford corners Inaros and could shoot him, but Filip ambushes him. Filip has a gun pointed at Ashford so if Ashford shoots Inaros then Filip will shoot him. Ashford apparently surrenders and is executed, refusing to bargain for his life.
Given that Ashford is apparently okay with dying and must have known that surrendering would lead to his execution anyway, why not just shoot Inaros?
Ashford chose to communicate something to somebody rather than die quietly.
If Ashford shot Inaros, Filip would shoot Ashford and no one would ever hear anything further from Ashford. However, after being spaced out the airlock, we see Ashford's wrist-mounted communicator first "Sending" and then "Message Sent". Presumably he used his time before being spaced to subtly key in or record a message, then sent it as he was being ejected from the ship.
What was he sending, and to whom? We don't know. But maybe it was something more valuable than Inaros' life, such as information about the ship or something he learned while on the ship that will help foil Inaros' plans.
(Images flipped 180 degrees; in the video the words are upside-down).
