Strange JSR-303 validation path

[nickarls]

This is not strictly an AS7 question but since I know you are all bored and looking for an easy challenge for a change ;-)

I have a

public class Master
{
   @Valid
   private List<Detail> details;

   public Master()
   {
      details = new ArrayList<Detail>();
      details.add(new Detail());
      details.add(new Detail());
   }

   public List<Detail> getDetails()
   {
      return details;
   }

   public void setDetails(List<Detail> details)
   {
      this.details = details;
   }
 
}

and a

@DetailValue
public class Detail
{
}

with a

@Documented
@Constraint(validatedBy = DetailValueValidator.class)
@Target(TYPE)
@Retention(RUNTIME)
public @interface DetailValue
{
   String message() default "{nada}";
 
   Class<?>[] groups() default {};
 
   Class<? extends Payload>[] payload() default {};
}

and

public class DetailValueValidator implements ConstraintValidator<DetailValue, Detail>
{
 
   public void initialize(DetailValue constraintAnnotation)
   {
   }
 
   public boolean isValid(Detail value, ConstraintValidatorContext context)
   {
      return false;
   }
}

and test it with a

   public static void main(String[] args)
   {
      Validator validator = Validation.buildDefaultValidatorFactory().getValidator();
      Master master = new Master();
      for (ConstraintViolation<Master> constraintViolation : validator.validate(master))
      {
         System.out.println(constraintViolation.getPropertyPath());
      }
   }

How come I see

details[1]
details[1]

when I trough the debugger in the DetailValueValidator ConstraintValidatorContext see the correct paths details[0] and details[1] being processed?