This question misunderstands what is "fixed." Your chart is a potential map, not a completed painting.
Effort matters enormously. A chart with strong Wealth potential but weak Day Master means the money is available — but only if the person builds the strength to hold it. Without effort (building skills, discipline, self-awareness), the potential never manifests.
Similarly, a "challenging" chart that's navigated with wisdom and persistence often produces a more extraordinary life than a "good" chart taken for granted.
Think of it like this: BaZi shows the terrain you were born into. Effort determines whether you build roads, plant crops, or leave the land barren. Same land, completely different outcomes. The chart is the starting point, not the destination.