The tendency to varicose veins is already innate in over 90% of our patients. So, it is not the defective venous valve that turns the vein into a varicose vein, it is the defective vein wall that leads to the expansion of the cutaneous veins and thus sooner or later to the defective venous valve and thus to the development of the varicose veins. Young people are also affected to some extent. The congenital lack of venous valves, which is also possible, is a very rare exception.