Humans are simply incapable of paying attention to a task for long periods if it doesn't involve some kind of interactive feedback. You can't ask someone to watch paint dry while simultaneously expect them to have < 0.5sec reaction time to a sudden impulse three hours into the drying process.
1. AEB brakes violently to a full stop. We experience shock and dismay. What happened? Oh, a kid on a bike I didn't see. I nearly fucked up bad, good job AEB
2. AEB smoothly slows the vehicle to prevent striking the bicycle, we gradually become aware of the bike and believe we had always known it was there and our decision eliminated risk, why even bother with stupid computer systems?
Humans are really bad at accepting that they fucked up, if you give them an opportunity to re-frame their experience as "I'm great, nothing could have gone wrong" that's what they prefer, so, to deliver the effective safety improvements you need to be firm about what happened and why it worked out OK.