After years of practicing meditation I have determined that focus is one of the most essential parts if meditation. Without it the monkey mind takes over and leads us in every direction possible accept for a focused awareness. If we have nothing to focus on....No mantra. No technique. No visualization. No focused awareness. Then we are merely day dreaming which is an unfortunate waste of time.
Giving the chattering mind a task is HUGE for me- like focusing on the breath. Sometimes just witnessing the thoughts come and go is pleasant in its own form but at times I tend to trail too far down one avenue of imagination so focusing on the breath or falling back on a mantra helps me refocus my efforts. Even when jogging, I find a mantra helps keep me going and I believe there's a form of personal transmutation happening internally when reinforcing the mind with these positive impressions.