What is “mindfulness”?
Mindfulness is being completely present in every moment. It involves cultivating acceptance and curiosity about one’s inner and outer-world. Mindfulness means no longer being stuck in the past, present or future. Finally, we let go of the pressures of who were or want to be. In this way, mindfulness is the practice of discovering who we really are without boundaries.
Why practice mindfulness meditation?
I think the purpose of training in mindfulness can depend on the individual. Traditionally, mindfulness practice is about awaking from suffering, which is caused by negative mental habits. Mindfulness practice is then seen as a way to work with troubling mental and emotional states. Therefore the cure for suffering is to be present and accepting with any mental arising which leads to a lessening of attachment to negative states.
However, other good purposes of mindfulness meditation are relaxation and learning how to directly experience our reality as opposed to allowing mental projections to disconnect us from our lives.
It is really up to the individual to decide what keeps them practicing, I cannot think of many wrong reasons for meditation and mindfulness practice but one big one is escapism. Mindfulness is about accepting reality and not running away from it.