You can always tell when an actor has grown a 'rhino skin'...

You can always tell when an actor has grown a 'rhino skin' to protect themselves. It comes across on screen, and they aren't believable. They're dead in the eyes because they've been told a million times that they're the greatest actor that ever lived. If you don't realise what's happening, and get your feet back on the ground, it can be the worst thing that ever happens to you.