IN most cities, the rationale behind introducing a self-service ticketing system on public buses is either to save money or increase efficiency. Not so in Beijing. Here the rationale - if there is one at all - appears to spend more money and confuse the public. Seven bus routes in the capital introduced self-service ticketing systems last week but, rather than get rid of the now surplus-to-requirement ticket sellers, the conductors remained in their booths by the doors doing absolutely nothing. Beijing commuters were thus faced with the bizarre situation of having to place their fare into an automatic ticket machine while the conductor, who only a week before would have sold them that ticket, stared off into space. ''What are these people being paid for,'' a young office worker said as he glared at the nearby conductor who was busying herself with her knitting. The bus route management companies dispatched hundreds of employees to bus stops along the routes to answer passengers questions about the modernisation drive. Asked why buses still had conductors on board when the sign on the side of the bus said ''no conductor'', staff explained the conductors were there to ''watch the doors'' and ''maintain public order at bus stops''. Quite how the conductors were supposed to maintain public order at some of the world's most chaotic bus stops, while confined to their small metal booths, was not explained. The real reason for keeping conductors on conductorless buses is obvious, the bus companies could not find alternative work for them and dismissing them was simply not an option. Although the bus routes have quasi-privatised under the contract responsibility system, they are still comparatively conservative when it comes to labour relations. It would be inconceivable for the bus companies to simply dump their long-standing employees on the street, without a job, housing, medical and welfare benefits. So the conductors still get to ride around in the buses ''watching the doors''. But the bus conductors are not the only people in Beijing with mind-numbingly boring and pointless jobs. The capital seems to specialise in creating useless employment opportunities. There is the person in the kiosk in subway stations employed to watch the escalator even when - as is usually the case - the escalator is not moving. There are the people employed at the gates of public parks and historical sites, one to sell tickets and another, only a couple paces away, to rip the ticket up and place it in a litter bin. Then there are the lift ladies who occupy just about every high-rise apartment building in Beijing. They sit in the elevator behind a small desk, occupying enough space for at least three people, pressing the buttons for the floors requested even though the residents of the building are quite capable of pressing the buttons for themselves. But the prize for the most pointless job in Beijing has to go the small state-run factory in the west of the city which still employs five people to organise the delivery of coal for the heating system even though the factory converted to gas heating two years ago.