Googler here. I want to apologize for the way that the recruiters and interviewers treated you. There were several anomalies in the story you describe. The delays in were unacceptable. There should only be one phone screen in most cases. At some point, without telling you, my guess would be that they transfered you from one job ladder to another (the second round of phone screens) even though you seem to have qualified for on-sites with the first two phone screens. The second two interview questions that you got were also unacceptable because they tested for prior knowledge, not general capability. Also, I have never seen an interviewer care about testing (but I never interview for the Software Engineering in Tools and Infrastructure ladder—maybe it happens there).

There are several similarities to my interviewing process with Google in 2018. Mine started off similarly, with a conversation with the recruiter where I learned that team placement didn't come until later. That conversation was okay, but it soon became more frustrating.

The first problem was that the recruiter started e-mailing my GMail, even though I'd communicated that it was not my primary e-mail account. But we got that sorted. Then, when coordinating the time for the first remote coding session, the recruiter had asked if a particular time worked, and I replied that time didn't, but listed several others that did. I didn't hear back, until I got an e-mail sent in the hour she had initially proposed, asking why I hadn't been there for the interview. I found the e-mail where I'd mentioned that time didn't work, sent it to her, and she apologized and re-scheduled, but it was the first (and so far only) time I've had a recruiter not pay enough attention to ensure the interview was scheduled at a time the interviewee was available.

When the remote coding session did occur, I still hadn't been informed that the format was a remote coding session. Perhaps the recruiter assumed everyone looks up Google interview prep and knows this, but Google wasn't my first choice of the places I was interviewing, so I hadn't. Like Ilya's 2048 example, the problem was one I wasn't familiar with in the slightest, and I didn't understand the task. Not knowing the format, I inquired about sample data, another problem… anything that would allow me to demonstrate my abilities. But apparently the format is to only ask one question, so the interviewer stuck with it until after 10-15 minutes I let them know I wasn't interested in continuing to struggle with a problem whose goal I didn't grasp for however long they planned to let me continue doing so.

Perhaps also worth noting, even if the task had been comprehensible, Google Docs leaves much to be desired as a coding platform. Something like VSCode's remote sessions would have been far superior. I understand Google probably wants to stick with their own products, but some flexibility would have made for a much-improved process.

Overall it was the most frustrating and least professional interview process I've experienced, out of a couple dozen in the past decade and 6 in the past two years alone. Some companies I decided I wouldn't want to interview with again because of the company, but Google is the only one where I wouldn't interview with them again because of the interview process… and I didn't even realize how extensive the process would have been, had it started off better, until reading this article.

It worked out okay in the end, though. I wound up working for my first choice among the companies I interviewed for at that time, and have learned a ton through that position.
Have the same experience as you in July-September in last year. But it's worth noticing that the problem during the phone-interview section usually checks only the basic algorithms, and you could ask a lot of questions about the validity and the complexity of your solution before writing the code. Also, AFAIK if you pass to the on-site section Google had provided the free online-seminar about the System Design section(format, which questions is mandatory, etc.) for the applicants. But last year they said that such activities were cancelled in June.
On on-site sections also you have not too many choices (ChromeBook vs whiteboard)

Also I found that there is no balance between sections, but the fail on one of them can really costs you the position. Some questions can be just reformulated versions of the questions from the phone-interview. Some sections can be much easier than others (Graph traversal vs implementing lazy-evaluated Segment tree). IMHO Googliness is much harder than the algorithms and System Design). Also, It's said that the applicant can be invited to the on-site section only three times, after that you'd be permanently removed from the candidates list.
Also I heard that complexity of coding questions slightly differs from SRE positions to SWE positions(harder)
UFO landed and left these words here
This happens in every big giant company, even I'm facing the same issues, hardly I tried more than 4 times the same company finally I had placed the same company.
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