-Processes and Tools: Criteo has been a bit behind on providing employees with efficient tools to help them streamline processes. This has definitely improved since I joined and I can see it is headed in the right direction.
Training: Again this is getting better, however training has definitely been a challenge for newer teams. Training should not only span the engine and products, but also job roles (AS, TS, BI).
Collaboration and Communication: depends on the team/business line. For newer teams, there has been more disconnect. There needs to be a bigger push to integrate all teams and knowledge share across teams.