She works really hard for crap pay. Why? She wants Leo to like her. So Willa wanting someone to like her, by definition, means she's not a sociopath.
So, she's redeemable.
Like a coupon.
“An Orphan Walks Into a Bar” · Season 1, Episode 1
In this episode: Walter Sherman (2), Leo Knox (2), Marshal Isabel Zambada (1)
CCooper
I'm sorry, sir, I-I can't seem to find my wallet.
[Leo glares at Willa, who produces the wallet]
CCooper
You stole my wallet?
You probably just dropped it and Willa was kind enough to pick it up for you.
[Walter is being chased by a criminal with a gun]
Shoot him, Isabel!
Why? He dropped his weapon.
He killed my robot!
These quotes come from Wikiquote's The Finder pages and are available under the Creative Commons Attribution-ShareAlike License.