This is the first big vaccine from AZ, so part of it is that they are just bad at the various practical bits of the process compared to the more experienced mul

This is the first big vaccine from AZ, so part of it is that they are just bad at the various practical bits of the process compared to the more experienced multinationals. So for example, problems with quality control made for a unnecessarily challenging analysis of trial data. Slowness in reporting details when possible complications showed up in during the trials made the US authorities really pissy and they've still not granted it permission for emergency use. And then there is their awful communications around the production issues where they spent like a month giving progressively worse and worse news to their customers about how much vaccine would actually show up. All those very real problems make for good padding to any article about any new issue about the AZ vaccine. So because it is simply easy news to write it will get written, and this helps explain why there are so many.