True, the Titans had just fallen apart, motivating Dick's return home. On the other hand, the Nightwing one-off that followed showed him giving up both that role and Batman, saying he wasn't good at either.
The only interpretations I could come up with were: a) a short bout of biological depression, and b) his Fabio-style hair was taking up a lot more time than he'd expected. As I recall, Alfred supplied a new Nightwing costume, and Dick got his groove back.