Similarly, in Clermont-Ferrand the main objective for the different levels of spatial planning is to form a stronger agglomeration that can restart economic growth in the face of a slowdown in key industries and the potential negative effects of losing the status of being an independent region. However, in a market economy, it is more difficult to ensure that land uses specified in the spatial plan actually occur. For example, while spatial plans may seek to keep specific parcels of land in farming, if returns from farming are too low, the land will simply be abandoned. This asymmetry points to a crucial challenge for spatial planning: blocking specific undesirable land uses is far easier than achieving desired land uses.