Money is a sedative. It improves life to a certain point, but past that point it's less effective. There's also the effects that chasing wealth has on your psyche, where accumulation of wealth requires fiscal discipline, and the more money you get the more reluctant you become to spend it, and you're driven towards the accumulation of even more wealth.

Perhaps you don't believe me. If so, how do you think the cultural meme of the unhappy rich person came about? What is it about the lifestyles of the rich that would get in the way of living life to the full?