What signs were there that he needed to be given more time? Winning the League Cup a year ago is irrelevant in the context of what they need to do, which is preserve their status as a Premier League club. The way they've been playing this season (without Michu for large parts granted) must be a huge worry for the board and fans, and sometimes a change is needed even if it seems like a downgrade at first glance.
Swansea are really, really struggling to create chances, and it becomes a very simple process of logic when you consider that. No chances, no goals, no points, relegation. We'll see if it works, but it's far from a decision which can instantly be dismissed as stupid.