Many of these companies are heavily debt ridden by buying up competitors, building new factories and refitting old ones. None of this is done with cash - its all borrowed money. Fine if they could service the debt through sales.
However there are two financial problems at the moment - banks aren't lending and people aren't spending. If they can't refinance themselves they go into administration. Administrators look to see what is best - if the company is viable they will close sections to make it more viable, or they'll break up the company and sell whatever they can.
I don't think a name like Wedgwood will disappear anytime soon. If there are investors who can prop it up, they'll get their reward when the economy picks up.