Economic facts that don't mean what you think they mean.
Lack of productivity has nothing to do with individual performance, but with automation, industrial capital, organization and regulation.
Spain suffers from an antiquated labour regulation, including perverse incentives. As an example, many companies refrain from growing over certain size because it triggers a nightmare of regulation and expenses.
Also there are other barriers... I could write about that for hours, but it's sad and I'm tired.