BMW did to an awful job of running it, but the company has lost money since 1975 when the government nationalised British Leyland.
I think there has been a lot of confusion and technicaly the company has not gone into liquidisation but it seems there is no choice but for this to happen. MG Rover cannot make money with Rover's, MG cannot make money without the bulk manfuacturer of parts i.e Rover.
So even if the company stopped making Rover's and concentrated on MGs they still wouldn't make money and there will be loads of job losses.
The government have offered £40 million for companies in the area to try and miimise the damage of Rover going as much as possible.