Odido’s Biggest Failures misses the key points, in my opinion: 1) a lack of "security by design" and 2) insufficient security monitoring.

By centralising and outsourcing all data to what appears to be a Salesforce Cloud solution, this was a disaster waiting to happen. If even minimal security monitoring had been active, someone should have noticed something. It is also possible that the security management department was competent, but senior management failed to understand or act upon the advice provided.