Meta Solution Engineer interview questions

I applied for a different role in different location but a week later the recruiter suggested me to apply for a role in my current city then I accepted and the same day I got a call from her. She replied at night. 1st round was a 25min online coding assessment, I spent 10 min and submitted. A few hours after I got an email from the recruiter and she arranged next round interview. Then I had a coderpad interview with solution engineer manager. The feedback was very positive. The next day I got invited to onsite interview. I finished my coding assignment and met another solution engineer manager, solution engineer and a sales director. The questions were also super easy. One week after I was asked to do another coding interview with a software engineer in HQ as the last round then I failed. I did resolve the problem but I guess it was because my solution was not efficient enough. All the interview questions are very basic and easy to work out. But they do care about the time complexity. When being asked to have additional round of interview after onsite, I did know they still felt not confident about my technical skills. I had 1-2 weeks for preparation between every two interviews. But I didn't really prepare for that long. Even though, I still think I have over prepared. Questions are far easier than my expectation. I just have not noticed these code efficiency issues. Again, that is the key. So that is my coding behavior problem. I get used to get work done fast and didn't use the most optimal way at the beginning. Overal, the communication with them is suprisingly efficient. I have not expected the company at this scale can move so fast. And it is quite straight forward, direct rejection is totally fine to me. At least I do not need to imagine and wait. This is a good chance but unfortunately I miss this chance. It is a good company but I am afraid I won't consider applying any more in the future. As I am 30 now, I do need to try more different types of companies but not be sticky to the tech giant only. To encourage the guys who failed like me, don't forget they also rejected the guy who made whatsapp.

I applied through the website, was contacted within 2 weeks and had a interview schedule with a software engineer from San Francisco office via internet. I didn't do very well at the coding and I didn't received feedback.