wheels You can stop in a shorter distance with a brake.
Being able to stop quicker allows you to cycle faster.
I've found that is quite a compelling reason not to have a brake, personally. Without one I can't ride as fast a) for the obvious reason of not having a brake and therefore having to be careful, and b) because of the lower gearing brakeless riding is suited to.
Saying that I do wear a helmet some of the time which is quite paradoxical for a brakeless rider in itself.
I've found that is quite a compelling reason not to have a brake, personally. Without one I can't ride as fast a) for the obvious reason of not having a brake and therefore having to be careful, and b) because of the lower gearing brakeless riding is suited to.
Saying that I do wear a helmet some of the time which is quite paradoxical for a brakeless rider in itself.