After sending L'Oréal Germany my CV (no motivation letter was needed), I have received an invitation to participate in an assessment center for the whole day after about 2 weeks. The day consisted of different tasks (yet typical for any assessment center): a self-presentation, a group exercise in English and a business case study. After completion of all the assignments you will receive an individual feedback by the HR team and (depending on your performance) they either send you home or to an additional interview with the brand/department they have chosen for you.