Dishonored’s shadows are never dark enough that the player completely disappears into them. Garrett could have a guard walk inches past his nose if it was pitch black; the same cannot happen here...
“We’re big, big fans of Thief. But in Thief, at some point you had to accept that hey, you know what, I’m invisible in the shadow even if it’s a little weird for the characters not to see me. And we tried doing playtests and felt that a lot of people were actually not sharing that. They were like, that’s kind of weird, they’re coming close to you and the NPC doesn’t see me – how come I’m invisible? Is the NPC stupid?”
“So then we went back to the whiteboard and asked, how can we fix that? And we thought of this interesting way where like, the further away you are, the more light matters. And so it kind of addresses that paradox that exists in Thief.”