Unfortunately inconsistencies are the nature of the game; requirements differ between countries, and within countries airports have different equipment (tech and policy evolves faster than the lifecycle of these expensive machines).
For real frustration try the BA flight out of NBO - when I last did it there were 4 security screening checks for SLF; screening at entry to building, screening to airside, screening at gate (airport), screening at gate (BA).
Or Kota Kinabalu, where they inexplicably mix screened departing pax with arrival pax and then have to rescreen everyone before they go down to gate
