According to Henepola Gunaratana's "Mindfulness in Plain English," our thoughts need a focal point to remain centered and efficient. Without a specific object for focus, the mind tends to wander aimlessly. To harness mental attention, it's essential to choose an object that is always accessible and present in our experience.
Gunaratana suggests that our breath serves as an ideal focal point for mindfulness practice. Observing the breath is effortless as it is a constant companion. This makes it easier for the mind to maintain focus and cultivate a sense of awareness in the current moment, thereby enhancing mental clarity and tranquility.