Majority of hardcore fanbase heard the leaked versions. Not even the whole fanbase! And that is like 5% of the people that will buy the album. The rest of the world deserves to hear those songs.
Also I don't know why you are disappointed. Those songs are not officially released, they were stolen from Sony servers and other places and illegally posted on the internet. Also you didn't have to listen the leaks.
Another thing MJ is dead so he can not record new music or finish unfinished demos (mojority of unreleased songs are in that form). Other songs that are mostly finished are in the hands of greedy producers like will.i.am and RedOne who refuse to release them.. so that leaves the Estate with limited resources. They picked the best they had that is almost finished and releasable.
Also you heard 6/9 songs BUT 4/17 tracks!
1. Love Never Felt So Good - UNHEARD
2. Chicago - UNHEARD
3. Lovin' You - UNHEARD
4. A Place With No Name - UNHEARD
5. Do You Know Where Your Children Are - UNHEARD
6. Slave To The Rhythm - UNHEARD
7. Blue Gangsta - UNHEARD
8. Xscape - UNHEARD
9. Love Never Felt So Good (Original Demo) - HEARD
10. Chicago (Original Version) - UNHEARD
11. Lovin' You (Original Version) - UNHEARD
12. A Place With No Name (Original Version) - HEARD
13. Do You Know Where Your Children Are (Original Version) - UNHEARD (2010 Work In Progress Version leaked)
14. Slave To The Rhythm (Original Version) - UNHEARD (2010 Album Candidate leaked)
15. Blue Gangsta (Original Version) - HEARD
16. Xscape (Original Version) - HEARD
17. Hot Fun In The Summertime - UNHEARD