Everything changes, nothing is permanent.
Waking up in the morning is a change. You are no longer asleep. You have made a transition, from one state into another. Each day is different, and although some days may feel similar, no two days are the same. Each moment in time is temporary. We shift from one moment to the next, with change acting as a cause and effect.
Material goods come and go. They may eventually break down, but they are not permanent. Over the course of a few years or a lifetime, relationships may come and go. They may grow stronger, or fade away. Nothing stays the same. Your feelings within a job may change, or your circumstances may change. Your emotions can, and will change. One moment you might be happy, the next moment you're sad. You may have a week or longer when you feel low, but that will change. It will all come to pass. No one state is permanent. We live, and we die. We are not permanent.
Holding on to anything in life will only prolong the inevitable act of letting go. Every element of life is constantly undergoing a metamorphosis, nothing is static. When we can let go of the idea of permanence, we empower ourselves to accept and ride the waves of change. Change is important in life. It can bring our desires to us, it can teach us valuable lessons, and it keeps us moving. Many of us fear change, or the idea of change. But in the realisation that everything is changing, constantly, and that absolutely nothing stays the same, we can appreciate that any change in our lives is just that, a change. That change will lead to another change, and as nothing is static, will in time lead to another change and so on. There is nothing to fear in this flux of life, because everything changes.