I think ultimately, the only source of value in the universe is in the experience of happiness or suffering. And it is therefore the experiencing of happiness or suffering which is the only possible source of the meaning in life.

And so the question of whether life is worth living is ultimately this: whether we have hope that we will have some measure of happiness in the future, or whether we can expect only suffering.

If people believe the latter, we call that "despair". And that's when people may choose to give up, and even to end their own life.

As mentioned in the chess analogy, the actual movements in chasing our happiness (i.e. meaning) may look different to different people at different times. But I think you can always collapse the meaning down into the question of "will this make me happy, or will this make me suffer?"