The interview process is hard. At least three rounds of interviews, each with at least two people. They are looking for people who will stay and if possible someday move up- Remember they have 300,000 people world wide so they feel that somewhere, someone with in Siemens already has the skill set for mid-level position and they have less risk by hiring from within. So an engineer might start as an intern in college and grow over the 30 years to VP of something.