It’s one of the greatest truths of life.
Life, is tiring.
That, sort of, derives from the first statement. I mean you are tired when you hike up a mountain, don’t you? You are tired, all the while you are climbing. You might decide to take rest a couple of times, or more, but the tiredness, it remains, all the while. Happiness, is when you get to the peak, and the cold gusts of air wash all over you. When you can look around, and down, and look at the progress you’ve managed to make.