Zalando Research is an internal team of researches, their work is primarily shared with the research community through publications: https://research.zalando.com/welcome/mission/publications/

In the case of Flair, research led to a reference implementation, which was then matured through internal use and open sourced to further mature it and get external feedback. While employer branding is a nice benefit, it is a positive side-effect, not the motivation in itself :)