A character might change and resolve their personal angst, yet fail in their quest as a result. Was it worth it? Depends on the degree of angst and the size of the failure. Another character might not resolve their angst; yet by refusing to change accomplish the goal. And even if they do accomplish the goal, it might have been a misguided thing to do, and is actually quite bad that they were successful. The character might not have been aware that the goal was a bad thing, or they might fail to achieve a good thing.
In addition, goals might be partially achieved or only small failures, and a character might resolve only part of their angst, or just slightly increase it.
The flavor of the story will ultimately depend on how all these elements stack up at the end, and offer you a palette of shadings, rather than just Happy or Sad, and Success or Failure.
--Melanie Anne Phillips