If you mean reviewing, then definitely yes. I'm in America so we don't probably have as high stakes of exams as you do, but the closest thing was probably the AP exams I took. I had a perfect GPA all throughout high school and felt that I understood everything. However, when it came to my results on my AP tests I did really bad compared to my expectations. I took exams in English, Statistics, American Politics and Government, U.S History, and Macroeconomics. On a 5 point scale I got 4's on my english, statistics, and macroeconomics exams, a 3 on the politics and government exam, and a 2 on my history exam. I received credit on three of the five I took, and I was expecting to get five out of five without doing any review. In the end my grades in high school couldn't matter less, but my AP scores really made a difference. So I say if you want to do well, study and review as much as you can because in as the example of my life shows, grades don't predict how you'll do on the exams that really matter. I got A's in all my corresponding AP classes, but clearly that didn't mean I was guaranteed to even pass my exams.
