See this thread on Flyertalk for more experiences: https://www.flyertalk.com/forum/u-k-ireland/2045283-passport-never-works-egates.html
There was some sort of change on the back end system in or around October 2024. As a result many people who were previously almost always rejected no longer experience any problems. This was reported on the above linked forum.
Yes, sometimes the algorithm hands the task to a human officer. It may have changed recently but in the past one human officer was required for every 5 e-gates that were in operation. This was why you would sometimes see some of the e-gates roped off despite long queues. I'm not sure what the one-way mirror was, as you can see the human officers who are working the e-gates, they are in the cubicles behind the manual immigration desks.
Regarding my own experience, my passport never worked at the UK e-gates before 2018, despite working perfectly in Dublin and all over Schengen. That year on one of my frequent trips, as I was boarding a flight out of the UK I was detained at the gate and interviewed by some British government officials.
They were very excited thinking that they had caught a criminal (they certainly acted like it), however they then realised I was doing nothing illegal. After that trip my passport has worked in the UK e-gates every time.
A similar experience was reported here https://www.flyertalk.com/forum/british-airways-executive-club/1930260-word-fuzz.html though the trigger for my interrogation was something different which I will not reveal on this forum.
I also read on a forum that my experience may have been a training exercise for new hires (that is to say, they may have already known I did nothing wrong, but they found something that in some circumstances would be suspicious and this gave them a pretext to stop me). However that would not explain why my passport suddenly started working in the e-gates after this incident.
They are now flawless with both my passports after several years of 90% fail rates. I've not seen a significant queue at LHR for them now, which implies they are working much better.
There was some sort of change on the back end system in or around October 2024. As a result many people who were previously almost always rejected no longer experience any problems. This was reported on the above linked forum.
On one occasion at Gatwick a man popped out from behind a one-way mirror and told me to take my glasses off (I didn't wear glasses for the passport photo). I assume there is a small team there who can override anything that a gate hasn't been able to match.
Yes, sometimes the algorithm hands the task to a human officer. It may have changed recently but in the past one human officer was required for every 5 e-gates that were in operation. This was why you would sometimes see some of the e-gates roped off despite long queues. I'm not sure what the one-way mirror was, as you can see the human officers who are working the e-gates, they are in the cubicles behind the manual immigration desks.
Regarding my own experience, my passport never worked at the UK e-gates before 2018, despite working perfectly in Dublin and all over Schengen. That year on one of my frequent trips, as I was boarding a flight out of the UK I was detained at the gate and interviewed by some British government officials.
They were very excited thinking that they had caught a criminal (they certainly acted like it), however they then realised I was doing nothing illegal. After that trip my passport has worked in the UK e-gates every time.
A similar experience was reported here https://www.flyertalk.com/forum/british-airways-executive-club/1930260-word-fuzz.html though the trigger for my interrogation was something different which I will not reveal on this forum.
I also read on a forum that my experience may have been a training exercise for new hires (that is to say, they may have already known I did nothing wrong, but they found something that in some circumstances would be suspicious and this gave them a pretext to stop me). However that would not explain why my passport suddenly started working in the e-gates after this incident.