> There are other things that can bring a site down, like [...] too much traffic[.] But generally speaking those things are rare and don't bring down an entire site.
I agree with your assessment, but I do want to highlight that this condition is not rare for Twitter. Load is very spiky, sometimes during predictable periods (e.g., the World Cup, New Year's Eve) and sometimes during unpredictable periods (e.g., Queen Elizabeth II's death, the January 6th US Capitol attack). It isn't going to cause a total site failure (anymore), but it can degrade user experience in subtle or not-so-subtle ways.
An aside on the "anymore", there was a time when the entire site did go down due to high-traffic events. A lot of the complication in the infrastructure was built to add resiliency and scalability to the backend services to allow Twitter to handle these events more gracefully. That resiliency is going to help keep the services up even if maintenance is understaffed and behind a learning curve.
I agree with your assessment, but I do want to highlight that this condition is not rare for Twitter. Load is very spiky, sometimes during predictable periods (e.g., the World Cup, New Year's Eve) and sometimes during unpredictable periods (e.g., Queen Elizabeth II's death, the January 6th US Capitol attack). It isn't going to cause a total site failure (anymore), but it can degrade user experience in subtle or not-so-subtle ways.
An aside on the "anymore", there was a time when the entire site did go down due to high-traffic events. A lot of the complication in the infrastructure was built to add resiliency and scalability to the backend services to allow Twitter to handle these events more gracefully. That resiliency is going to help keep the services up even if maintenance is understaffed and behind a learning curve.