When reducing contributions and social security, minimum wages fall. It sets in turn 
downward pressure on wages just above minimum wages. It lowers purchasing power and tax revenues. When taxes are reduced, the public sector must exempt. When the purchasing power of the public sector and its staff declines, consumption of private sector goods and services declines. Then the private employers must also lay off staff. Which leads to further reductions in tax revenue. So the recession was started by stinginess towards ordinary people.
A bourgeois objection could be that reduced allowances cause people to apply for jobs they would otherwise have been too good for. My objection is that the control systems are so good that people are still forced to take jobs if there are any. Then, since the 90s, we have a pursuit of an equilibrium unemployment rate of 5% to keep inflation down. When as many as 5% get reduced social insurance and benefits, this starts the purchasing power-destroying spiral of recession. The alliance has tried this policy since 2006 and the result is sky-high unemployment, falling wages and recession almost all the time.
Although man has a policy of full employment, there are still enough people collecting social security or benefits as pensioners and sick leave that a reduction in their benefits would create a recession.
In addition, is a high social security fund in a society with full employment but with a mixed economy is of the utmost importance so that a recession is not worsened by too low social insurance which gives the recession further reduced purchasing power.
System but not least fighting for large income differences between those who work and those who cannot work against a healthy ideal of equality and solidarity.