This is about my experiences while applying for Amazon SDE New Grad roles in EU for the past couple of months. I have also previously applied for internships with them.

I have observed that the entire process is very very unprofessional and based on the few telephonic rounds I have had, I would say very mismanaged as well.

Key events / stories that made me jump to this conclusion:

• 9 times (including new grad and intership applications) I have finished all three OAs within 96 hours of receiving them. The status on portal changes to "Under Consideration" and stays the same for 4-5 months after which either a) I am called for a telephonic interview b) rejected. Note that all times, I have had perfect score on all OAs (can't say about OA3). Even if you get a call after many months, they expect you to conduct their interviews in the same week and if you cannot, ta ta bye bye.
• This is the most recent experience. The interview was for a very specific role, and I was not communicated about what the interview was supposed to be. I asked my recruiter plenty of times, if it is supposed to be standard DS/Algo round or would it be focused on the background knowledge for the specific role - no single response. It doesn't end here. During the interview, the interviewer asks me if I know what this round is supposed to be, because she doesn't know either. We anyway proceed to a DS/Algo question - a very standard one. And after suggesting the optimal solution, she tries to push me along a simpler implementation albeit with more (runtime) complexity. I point out that despite the simplicity we add some complexity due to a specific step, and she disagrees. However, I implement her solution and she agrees the implementation to be correct. I get a rejection mail 10 days later.
• Another very recent incident. I am told by the recruiter that I have cleared the OA and will receive an email from the scheduling team. Next day, instead, I receive the email from the same recruiter saying "thank you for speaking with us, but we decided to proceed with others". WTF?
• Another telephonic round for an internship in an optimization team. The interviewer asks me for optimizing a standard leetcode problem. I try my best but she isn't convinced. Her issue? I should have used ++i instead of i++ in the for loop. I explain her that while I understand your point, but point out that recent GCC versions have this basic optimization turned on, and thus should not yield any improvement practically. Result? Rejected.

I assumed that like other FAANG companies, Amazon would have optimized its hiring process, and it maybe the case with US and APAC offices, but definitely not with the EU ones. This post is not mean to deride the work done by engineers at Amazon EU.
I just wish to share my experience and wish to know if anybody else has had such issues or am I special in that way. I would have loved to share this feedback with my recruiters, but as always, all communications are from unattended no-reply addresses :)

And lastly, I would be thankful if anyone can point out any mistakes I might have committed.