I think this system will also give a audio warning if it is not able to record, say due to a broken memory card. at least today most modern systems would do that.
In the old days a dashcam would sit there and do everything you expected it to do, including LED lighting up / flashing and so on, but it would not be recording.
Hence why in the old days we argued for regular inspections of the memory cards, to make sure everything was fine.
I have lost count how many times people have come here saying " so i got this cheap dashcam 3 years ago and now i had a accident and i just found out it have not recorded anything for 3 months "
I remember me looking over a memory card in the card reader on the computer would not take many minutes for a 128 Gb memory card, focusing on start and stop places of drive sessions was in accepted places and not just suddenly in the middle of some random road.
You can of course not inspect every recorded file as that would take as long as it took to record them, and it would be very boring, so after sampling start / stop session files i just did a few random files just to see if they would play in a regular software player on the computer, only playing seconds of each file.