How challenges of human reliability will hinder the deployment of semi-autonomous vehicles

•While automated driving systems have the potential to reduce traffic collisions by minimising human errors, safety performance is not necessarily the primary purpose of this technology and can instead be seen as a constraint.•Semi-autonomous driving can have a particularly detrimental impact on driver distraction levels, with situational awareness significantly reduced from Level 1 to Level 2 automation.•Some studies link autonomous vehicle usage with risky driving behaviours, which includes sensation-seeking or driving when impaired.•The interaction of these autonomous vehicles with third parties, and in particular vulnerable road users, will be problematic in the absence of implicit cooperation rules. This perspective article explores the impacts that the transition period to fully autonomous driving will have on human reliability and how these challenges will become major hurdles in the safe deployment of the technology. In particular, the analysis focuses on the potential contribution of Automated Driving Systems (ADS) towards safety, the specific role of human errors in this field and how driver distraction and its associated risks are exacerbated by the introduction of ADS. Additionally, the link between Autonomous Vehicle (AV) usage and risky driving behaviour is discussed, as well as the issue of interaction between AVs and other road users.