Before the Oslo “peace” accords, there were no hilltop outposts. When a group of Jews wanted to start a new town in Judea and Samaria, on empty government land, they did so, and the town immediately received governmental recognition.
After Oslo, in order not to raise the ire of the Western powers, Israel stopped building new towns in Judea and Samaria but continued expanding old ones. Threats from such initiatives as Oslo, Wye, Annapolis, Camp David Two, etc, etc., led to the creation of “outposts,” new towns built from scratch outside the boundaries of the established towns of Judea and Samaria. The thinking was this: If we don’t use it, we’ll lose it.