France may be different. My problem was that only a quarter of my degree was maths. It needed to be one third. One extra course. Plus you could only ever talk to call centres who were reading from a script. If I was going to invest in a year of child care as well as my time, I wanted to be sure I was making the right decision. Pity as I always had an aptitude and had good grades at maths A level, lived in an area that struggled to recruit maths any teachers, and none of the maths/stats I did at University would have been relevant at GCSE.
Its easier now. I think as you can train in a school, so you just need a school to take you, but that was only just coming in when I was looking. I had to do some work in schools at one point, talking to large groups of South London teenagers, and apparently (or at least the teacher with me said) I was fine at getting and keeping their attention. I think I would have liked it, and having school holidays would have helped a lot. I would have wanted to teach maths though, as it is clearer, more cut and dried than school level economics. (And I would have hated teaching primary.)
But all a long time ago.
I don't think it is uncommon for different children to like different teachers. Because different children often need different approaches in order to feel secure about maths.