Happiness can take a person to success.
What need to be known is that happiness needs modified in approach so the success need to be redefined that provides long term gain?
Happiness is a satisfying feeling, if I have put enough effort in my best honesty I may not immediately get the right result but if satisfies me there is a probability of seeing a light whereby a slight modifying the approach would come closer to the desired result.
If we have taken a project for instance and are passionate to complete soon, making many attempts we at time feel restless which is outcome of passion but yet in the end of day once we are drawn out from the subject, a satisfying feeling crops which is happiness.
Success on the other hand is the desired goal which is viewed as such which itself could have a flaw. We make effort and see the track going away from the desired goal. There are infinite parameters to measure the output goal which is not a dead end. Hence if we have deviated from the original path we still can measure other parameters to identify if there is an error in concept or the result for modifying the approach.