so here in Germany we have a 50% participation (presentations in class, handed in homework and answering questions or giving input in class) and 50% to the two exams you write each year. I am really good in my exams but raising my hand in class and saying something makes me incredibly anxious. Therefore I would be happy if exams counted more, since my grades wouldn't be dragged down so much. I usually only amend my participation grade by handing in homework or essays, but that takes up so much time outside of school, I sometimes hate my life, whereas people with no anxiety get good grades because they are able to just say random stuff (sometimes not even relevant) while they don't put in as much work as I do. This is why assessing participation is hard and with biased teachers (it's impossible not to be, let's be honest) it's sometimes not easy to understand why someone got a better grade or a worse grade...
I for my part always wished only my exams would count, whereas some of my friends are thankful they can higher their grades through participating...
And even tough it annoys me so much I don't see any other way to do it, because this policy gives 50% to those good in exams and 50% to those who maybe are just good at participating.