A very prosaic description of the 'hedonic treadmill' (aka hedonic adaptation) which, at its core describes how the thing (product/service) that made us happy yesterday will eventually stop making us happy, as we yearn for even more/better. Those working in the innovation & service design space both fear and lean into this truism every day!

"When we have what we wish, we do not stop wishing. We grow accustomed to everything that we have; the same possessions do not retain the same value, and no longer affect our taste in the same way. "
- La Rochefoucauld