Why 3 Episodes?

I just finished and actually liked the mini series with all its flaws, but especially in the last episode i felt that there was too much going on to fit in in 78 minutes.
Why didn't they do an 8 Part or even 6 part series?. With all the content they easily could have thrown in 2-3 seasons of 10 episode on the channel and it could have explored even more stuff by also expanding all that has been crammed up in 3 tiny episodes