Mettā Meditation, significantly, commences with expressing love and compassion towards oneself. This is necessary because a person must first of all love and be compassionate towards her or himself before being able to radiate mettā to other beings. By mindfully practicing the Lotus Greeting, compassion towards oneself is strengthened.
Simultaneously, our sraddha in the Buddha Dhamma is advanced. Sraddha is crucial, especially when encountering trials and tribulations, and challenges in life. Meditation practice enables us to develop a spiritually strong fortitude to face the negative mental, emotional and physical experiences we are likely to encounter from time to time in life.