Then I don't think you're paying attention to everything that gets reported on here. The vast majority of issues, if you look, come from people talking about the North West. From people asking for help with prosecution issues to service disruption (remember that the North West was falling apart before the May timetable change) to comments about rude/unhelpful staff and issues with things being broken and not fixed.
As for why? Well, even today more than fourteen years later, Northern still have two different controls one in York and one in Manchester. They still, I think, have staff on different contracts some set up by First North Western and some by Arriva Trains Northern. There is still, on the West, distrust of management hanging over from FNW days that isn't quite as prevalent on the East.
You might not have noticed but my experience and the experience of others is that Northern is a very different animal in the East than it is in the West.