Here's the deal with professional coaches:
They are not always to blame, but you can't fire the entire team (or even the majority) so to get their attention you make the move you can make. Angels are not performing, so what do you suggest ownership do? Just keep hoping something will change season after season? The GMs are making moves for quality players like Greinke, Wilson, Pujols, and Hamilton (and going back even Teixeira), and the draft has yielded Trout but it's just not happening on the field.
What do you suggest?