Teads Creative Designer interview questions

I thought the recruitment process and HR communications were all great up until I had my series of in-person interviews... which was followed by a creative test/homework. After I submitted the assignment, I was told that they “wanted to seek more candidates before moving forward”—I had taken time off work to go interview with several Outbrain employees + spent a decent amount of hours on the homework. I feel like they shouldn’t have asked me to do free labor until they had a good pool of candidates. Seemed like I wasted a lot of time and energy... the worst part is that the homework was for a real event coming up. I just expected them to be more considerate of my time,