Salt makes sweet things sweeter. A little contrast makes everything more itself.

Contrast is how anything becomes noticeable. A pinch of salt does not add sweetness, it gives the sweetness an edge to be measured against, and the same trick runs through everything: quiet makes noise land, effort makes rest feel like rest, a little difficulty makes an easy day obvious. Remove all contrast and everything flattens into the same shade. Even good things stop registering when nothing sits beside them.

If something enjoyable has gone dull, try adding a bit of its opposite rather than more of it. Take a break long enough to miss it. Do one hard thing in the morning and watch what happens to the afternoon.