People often chase happiness in life and social scientists seem to measure individual or collective happiness as some kind of measure of how well a particular demographic, country or other group is doing. Meaning and fulfilment are completely different things from happiness but are often confused for one another. Sometimes the path to fulfilment or self realization can lead to happiness but are often the path there is filled with tribulation and stress.

Judging a fulfilled life is hard to do. Someone can sit and play games or watch TV all day and be perfect happy doing so but after some time for most people there's an emptiness or a lack of accomplishment. Hedonism is ultimately empty, often does not lead to positive social reinforcement from one's peers. You can only sharpen a sword against stone and smooth seas do not make for a skilled sailor. Generally individual humans yearn to be useful to the clan, tribe, troupe, church, country or other social group and that requires making a contribution or having something meaningful to bring to the table. That in turn means work or self-improvement.

Happiness is an end state that can result from stimulation or work and reflection. Stimulant happiness is usually gone once the source of entertainment is removed and leaves one longing or chasing that feeling again. Happiness from fulfilment can sit with someone in an empty room.

Do not chase simply feeling good, chase meaning and fulfilment. If it's difficult to do chances are it's the right direction.