In the film Terminator 2: Judgement Day by James Cameron a liquid metal robot assassin - the most advanced of its kind - stops just momentarily to look at an inanimate mannequin in a mall:
Why does he do this? Even though you don't ever see his "view", one would assume he would have all the latest software for detection and threat assessment of targets and this was clearly neither a target or a threat so why pause? Why is he not furrowing his liquid metal brow at the standing mannequin behind him who - if he was a threat, has already got the jump on him? Or every inanimate object for that matter? Ridiculous.
As an aside - why do the liquid metal terminators in 2 and 3 come through naked? I remember some spiel about the time displacement only allowing live things to go through, so yeah Arnie and Kyle Reese go through naked as they have live flesh - but a T1000 is all liquid metal. Surely they could have approximated 20th century clothes in the future to send them through in a less overtly suspicious manner? Again, ridiculous.