Mass immigration does now work yet the EU will continue regardless
The reasons why Spain availed itself of the safeguard clause are two fold. The first reason is the extremely high unemployment rate in the country, which has persisted over an extended period of time. The country has the highest unemployment rate in the EU at 21.2%, as announced by Eurostat in July 2011. In addition, it also holds the highest ranking for youth unemployment with 46.2% of people under 25 being unemployed. The second reason is the economic situation in the country. Spain suffered badly from the economic crises and still cannot recover. Their GDP growth lag behind the average of the Eurozone and in the first quarter of 2011 was only 0.3% in comparison with an average of 0.8% for the Eurozone. Furthermore, the country is faced with the urgent need to introduce further budgetary constraints, which will not encourage the recovery of its economy and growth of employment rates.
This economic background also saw a tendency for a growing inflow of labor migrants. The number of Romanian nationals resident in Spain increased from 388 000 in 2006 to 823 000 in 2010. Furthermore, despite low labor demand, the inflow of Romanian citizens continued, thus resulting in more than 30% unemployment rate among them. Against the background of slow economic recovery and high unemployment rates, this posed a considerable burden on the Spanish social security system and seriously distorted the labor market.
Further reading http://www.zei.uni-bonn.de/dateien/discussion-paper/dp_c217_kraleva.pdf