why different classes can equilavent to each other and can read same property value

Question

For example in this case;

@interface Anotherclass : Base
@property (nonatomic, strong) NSString * name;
@property (nonatomic, strong) NSString * surname;

@end

@interface SomeInfo : NSObject
@property (nonatomic, strong) NSString * name;
@end

SomeInfo *sInfo = [userInfo objectForKey:Notification_anotherclassobject];

why sInfo.name properly casts/ works? is there an explanation?