Are Russians desperately lacking airport security?

I am still waiting for the explanation of why are the passengers arriving to Germany from Moscow subject to a second security check in Germany? Is it because the Russian airport security is doing a bad job, or because Russians sell terrorist equipment in their tax-free airport shops? Why is the Russian security check adequate for a Lufthansa flight from Moscow to Germany, but not adequate for a subsequent Lufthansa flight from Germany to Lisbon? I am sure the brusselcrats have a perfectly logical explanation for this idiocy.