Our current moment can either be of perpetual joy or sorrow based on how we treat it. That's not to say that we always control it. But we have more control than we think. If we pay attention to it, we can build memories, notice opportunities and learn lessons that are extremely valuable to us as life goes on.
If, occupied with a better future, we ignore the moment, we can look back at it with regret, not realising all the things we missed out on. Because life usually gets less free as we grow.
That's the idea: being present is such an underrated tool in living a life you'd love, especially in hindsight. No matter what is happening, there's value in being with it. For someone with an overactive mind, being present is something that has helped with my productivity, the quality of my relationships and has improved my overall quality of life. It's an extremely important skill.