Two very popular TV shows which have lost their way (IMO, of course):

FRINGE. Jump 20 years into the future and leave every single aspect which made the show a success behind? Seriously?

THE GOOD WIFE. Disrupt the entire flow of the story so far and drastically undermine the strength of one of its most important supporting characters with a story thread which introduces her sadistic former husband and makes her look like a wimp and makes the whole show lose focus? Really?