Unclear why if statement doesn't work

Can somebody explain why this doesn't work:

int nrSegments=[segment valueForKeyPath:@"iteneryLegs.@count"];
    if (0==nrSegments) {
        [self removeSegment:segment];
    }

but this does?

int nrSegments=[[segment valueForKeyPath:@"iteneryLegs] count];
    if (0==nr开发者_开发技巧Segments) {
        [self removeSegment:segment];
    }

Because valueForKeyPath:@"iteneryLegs.@count" returns an NSNumber ?