What's the point if flights are still unchecked?

[Aberforthsgoat]

Heard an interview on the radio with a guy who travelled back from.new York this week. He started displaying symptoms during his journey but wasn't checked or screened coming back into the UK.
He has now tested positive
Am I missing something obvious?
Why are we all giving up seeing our family when this is happening every day, probably multiple times a day?
People keep commenting on how New Zealand have managed to contain and eradicate it as though it's amazing but I'm really starting to feel like it's not amazing, just common sense which they followed and we didn't

Is there a reason this is allowed to happen which I'm blindly not seeing?

Probably won't make much of a difference. I don't think there are many parts of the world where the virus is more prevalent than in the UK

Meanwhile, this is one passenger’s experience of what it’s like to arrive in Hong Kong, arriving from Paris via London :

threadreaderapp.com/thread/1260784481159442434.html