I disagree - if they are covering for a minor, understood and embarrassing mistake, then it does not mean they haven't learned lessons or that they aren't improving those standards and changing processes internally. It simply means they don't want to talk about it to the public, and want to keep it off the 6pm news.
I'm not saying they *have* learned any lesson or that there isn't incompetence/laziness somewhere. I'm just saying that trying to keep the incident low-key is not itself an indication of that.
As someone who has worked in IT operations, there are plenty of times where I have seen a near-outage occur because of a bad process. And many times, the offending team would quietly get their shit together but also not publicize their mistake, so as not to incur the wrath of execs.
