Many have been saying that the Olympics were a total failure for the UK economy. That is not true - most people have been told so, ignoring the statistical data and the long term effect of the venture. The Olympics have caused an increase in the national output ( also known as potential output) leading to an expansion of the economy which leads to long term growth. Furthermore, the domestic demand has increased significantly (not compared to the cost of the Olympics but to the current situation - recession) which is the main component of the aggregate demand - aka short term growth. As you can see the cornerstones are placed, it all depends on the consumer confidence to get the UK out of the recession now.