The level of subsidy is important. In cases where a direct subsidy for STBs is part of the Help Scheme, there is the risk that the subsidy has an inflationary effect on the STB market, and is absorbed by the manufacturing and distribution chains. The Help Scheme should not rely solely on the horizontal retail market for distribution of the STBs when the timescale for switchover is short – it may be necessary to generate the cooperation necessary to achieve a scaled rollout through a specific retail scheme.