How to get a harder Why?

In one of Brooke’s podcast she mentions having a hard Why. How do we get a harder Why? What I mean is a couple years ago I completed a big goal that I had been working toward for almost a decade.
Now I am not feeling any desire. I have a why…without getting into details, it is financial security. But am finding that I am not feeling the juice or desire to keep me moving toward my goal. What can I do to get a harder Why?