Since I've still got tons of WALL-E stuff I want to discuss here on Tumblr...
This is something I've talked a bit about on a WALL-E-themed Discord server, but we don't talk enough about how of all the reject bots, I think D-FIB and HAN-S are the darkest ones, considering their respective malfunctions.
Like, when we see D-FIB in the repair ward being tested alongside EVE and BRL-A, she sets a test dummy on fire. Most kids may think nothing of if, but...
She's a defibrillator, and she's setting stuff on fire.
She's supposed to save lives.
And if she's in the repair ward to try and fix that malfunction...well... something pretty tragic must have happened that led to the discovery of it in the first place.
As for HAN-S and his malfunction, well, let's hope whoever was unlucky enough to have him as a masseur survived the incident.
But you know what, I believe that fighting the Stewards is D-FIB and HAN-S's redemption in a way. In doing so, they both saved the lives of their new robot friends. We later see HAN-S massaging a fallen passenger and D-FIB helping pass the plant along.
So in the end, D-FIB and HAN-S ended up being lifesavers to everyone both human and robot.