I always try to make people understand the logic of maths. In the first place, it will make things more fun and they might start to like it. But a more practical reason is that if you just follow the rules without understanding things, you have to learn huge amount of those rules in the end, and then in my experience students start to confuse those rules and can't keep a structured overview of it all. The more you grasp of what lies underneath, the less you have to remember
It's cool that you're learning Swedish btw
Edit for afterthought: if people will not pursue maths after school, the useful thing they got from it is the ability of logical, analytical thinking. Making people only learn the rules causes them to develop that ability to a lesser degree, and that would be a bit of a waste