It's just all so predictable, isn't it? :( https://twitter.com/LeoKelion/status/1273591281470537728
"Following rigorous field testing and a trial on the Isle of Wight ..."

This begs two questions:
- did the app go out to trial despite the results of the "rigorous" field testing, or
- was the "rigorous" field testing not fit for purpose?
Why is the app being abandoned? Two more questions:

- the mobile app portion wasn't viable (eg a battery killer), or
- they had trouble with the centralised backend
Now, the centralised backend is very straight-forward tech. If they couldn't get that working, that's indefensibly bad.

From the reported features, it's not supposed to be doing anything that's difficult to do.
It's feature-set is reported to be small, so the main challenge is scaling it to cope with the required volumes of incoming data points.

The #ukgov should have chosen its commercial partners to provide that experience.
If the mobile app wasn't viable (e.g. it was a battery killer, or it collected false-positive contacts), that should have come out during "rigorous field testing".

Those are not difficult things to QA.
Did the trial on the Isle of Wight showed up fundamental issues? I'm not talking badly-written code. I'm talking an app that couldn't meet its requirements.

If yes, how did those issues get through the "rigorous field testing"?
I am treating "rigorous field testing" as a separate phase to the Isle of Wight trial.

By all accounts, the Isle of Wight isn't representative of the rest of Britain. There's no credible way to claim that the trial equates to rigorous field testing.
"This is a problem that many countries around the world, like Singapore, are facing and in many cases only discovering them after whole population roll-out."

That says that the problems are already known. So why did #ukgov repeat them?
"[We will] ... develop an app that will bring together the functionality required to carry out contact tracing, but also making it easy to order tests, and access proactive advice and guidance to aid self-isolation."

Scope creep after total failure to deliver.
I've seen this behaviour before in tech firms w/ terrible product management.

When they utterly fail to deliver something, instead of getting that delivered, they promise something with many more features than what they've already failed to do.
These newly-announced features aren't essential for an MVP. They could be added quickly in the weeks that follow an initial release.

For MVP, the app could simply give users a number to call, that puts them through to the contact tracing team.
. @MattHancock is then quoted as saying "The NHS COVID-19 app has undergone some of the most rigorous testing in the world".

If that's true, he's practically admitting that the app went to trial despite the test results.

It can't have gone because of the test results.
The most-likely root cause of this failure is the HIPPO effect: someone pulled rank, and pushed ahead with a technical solution that could never meet the requirements.

Because, otherwise, this #ukgov statement is misleading wrt the quality assurance work that was done.
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