Hilti Group Technical Engineer interview questions

Interview process lasted for 4 months, the longest ever experimented. In total I had 8 calls with HR, PM and Technical Engineers. Firstly a first contact by phone, then assessment in 4 people with a business case, then 6 different interviews everytime with the same contents and questions. I've received positive feedbacks every time, and Hilti expressed the interest in keeping in contact and getting to the next step. Till the last time where everything went positively as the other times but I received the email telling me that unfortunately the selection moved over me for the role, because another best fit has been found. The mail also said it was possible to request a structured feedback: I've asked for it more than 3 weeks ago and still no answers. If I would have applied for NASA, maybe I would have had a faster response and a smarter selection process.