I recently failed a CS coding test. I was asked to solve a problem in 10m. I solved it in 20m and was rejected. I came up with a solution and communicate it rig

I recently failed a CS coding test. I was asked to solve a problem in 10m. I solved it in 20m and was rejected. I came up with a solution and communicate it right from the start. My solution was totally clear and readable. I just needed time to warm up and attentive to my code. I love CS. I love solving problems and reading books about Algorithm and Data Structure. I implemented them from scratch as a hobby. But the interviewer guy is not caring about that and said process is process. I felt disappointed at first but felt lucky after that since I wouldn't want to work with those people in the future.