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by 256_ 694 days ago
> While we had regression testing in place, those tests failed to alert us to the change in functionality because the regression tests were scoped to workflows and functionality instead of the content/structure of the random value. [...]

> Unfortunately, no reviews were done to compare the legacy random value implementations with the random value implementations in the new system for every scenario.

In other words, they didn't do proper testing. At the bottom of the article they suggest they're going to improve it.