Why a perpetual magnet engines do not work?

Question

A sample of this motor:

[https://www.youtube.com/watch?v=LXBYMiNH1nE](https://www.youtube.com/watch?v=LXBYMiNH1nE)

In: 87

Answer 1

My understanding is that friction will always be a factor, and as such, ultimately, any perpetual motion type machine would be brought to stop because of it.