Insight: when we perceive our personal growth and we see our self development augment itself, we are happy. When we see ourselves or perceive ourselves to be degenerating, we are unhappy.
Then the question:
What do we really want a a final end– happiness or self development?
Or are the two things like an interconnected flywheel and yin-yang; both powering the other?
Also perhaps when we perceive that we aren’t growing and developing ourselves into something further and beyond, we become frustrated and that frustration (unhappiness) becomes the spur to motivate us to seek that happiness (self-growth and self-development?)
It is self development which we seek, and happiness is the means to that end!
Because when we witness and the self developmental growth becomes factual and true in our eyes, we get a spurt of happiness (serotonin, other hormones and bodily-brain chemicals). Thus in order to feel the happiness, we keep striving for more self growth.
So happiness is the drug which addicts us, and self growth and self development is the true goal and end into itself!