I Want You To Introduce Yourself Before I Add You As A Friend

So many people on here choose not to share any information about themselves on their profiles...and that's fine....Their choice. But I really don't understand why people send a PM saying things like ' I think we can be friends' when they don't tell me anything about themselves! If my profile interests you or a post of mine....then tell me so I know why you've chosen to get in touch! Coz if I click on yr page and can not find anything about you.....im not going to reply.