Some (but not all) guerrilla and/or terrorist leaders subscribe to a doctrine that while that while they cannot use force to immediately destroy the forces of their opponent they can inflict a heavy enough cost over time to make their opponents capitulate. Others use attrition as a point of operational buildup for a conventional strategy of annihilation, like the PLA's Huai-Huai campaign that destroyed Nationalist strength in Northern China and set the stage for the KMT's flight to Taiwan. Sometimes, however, attrition is not an option for a guerrilla leader. George Washington was put in the problem of an army that could not fight the Redcoats head-on in a battle of annihilation but could not maintain itself long enough to win a war of attrition.
The main thrust of Daveed Gartenstein-Ross's new book suggests that AQ believes it can win a war of economic attrition and sees itself through the framework of a war of attrition. I haven't read the book so it will be interesting to see how Gartenstein-Ross develops this thesis.