The Ofek satellites are mainly intended to give Israel a spy satellite capability independent of the United States (which has traditionally provided spy satellite data, but not always as much as Israel wanted.) Currently, there are also several commercial photo satellites available, that will provide pictures on demand, and for a price. But these satellites are not always able to provide the kind of detail, and timeliness, that Israel wants.
The failed Ofek-6 launch cost Israel over $100 million. Israel builds its own boosters, based on their Jericho ballistic missiles.
Israels attempt to launch a new spy satellite, Ofek-6, failed on September 6th. This is the second Israeli spy satellite launch to fail. The 1998 launch of Ofek-4 failed also. Ofek-3, launched successfully in 1995, remained functional for five years. Ofek-5, launched in 2002, is believed to still be operating, as it was designed to last for eight years. But Ofek-6 is thought to have a more powerful set of sensors. Moreover, these satellites orbit the earth every 90 minutes, meaning that having more than one enables you to get a more continuous look at whats going on down there. At the moment, Israel is particularly concerned about what Iran is up to in the areas of ballistic missiles and nuclear weapons.