Do 12th Board marks matter for admission?

Don’t Universities get an estimated analysis of how much you’ll get on your Boards from your teachers at whatever school you go to since by the time you begin to give your Board exams you find out if you got in or not? What would happen if a student got a percentage lower than the estimate given by the school? How much do 12th midterm marks matter for admissions? I know it’s a lot of questions but I’m just really stressed because I’m new to all of this and I still have to take the subject tests…

@iamdaone 12th midterms and pre boards do matter a lot. Some universities will not even ask for predicted grades. U would get the offer of admission before 12th boards where the minimum percentage required would be mentioned.(which is not very high… 87% in my case)