Income is what supports and ’causes’ sales. When income falls, sales in the first instance need deficit spending- spending that exceeds income- to grow employment/output from prior levels. The GDP forecasts include income/sales from public deficit spending as well as private sector deficit spending. The risk I see is private sector deficit spending falling short of the (implied) forecasts:

The euro area is also at risk that total deficit spending will be insufficient. Public sector deficit spending has been much lower than in the US, and private sector deficit spending has been limited for a number of years: