We live in a world that is set on progress and change and increase. CS Lewis called it The Myth of Evolution (making no comment on the similar sounding science) saying that we've convinced ourselves that these things are always improvements.
When it comes to my bank account if the balance has changed from what I was expecting it to be, it'll have gone down more often than up...
The Preacher in Ecclesiastes sees the world differently.
He sees the pursuit of these things but considers them to be wearying and evil and awful. Better, he says, less than more. Having more stuff and more work and more money and more words and more life just makes things more disappointing, increases the loss at death and weighs you down to the point of despair.
We want the story to be true but it's simply not. Lewis: "It appeals to the same innocent and permanent needs in us which welcome Jack the Giant-Killer. It gives us almost everything the imagination craves - irony, heroism, vastness, unity in multiplicity, and a tragic close. It appeals to every part of me except my reason."
Better he says to be dead than alive, and ideally to have not even lived. That, however, is outside our power. He says even (shockingly) that it'd be better to be stillborn than to live two thousand years or have one hundred children.
The most disturbing film I've ever seen is Ashton Kutcher's The Butterfly Effect. Kutcher's character seeks to fix problems in his life, travelling back in time to do this. Each backward step repairs something but causes disruptive ripples beyond... so much so that he eventually decides the best thing is not to be born at all. It makes me shudder, but it comes straight out of the pages of Ecclesiastes.
What then can be done if you are alive? The Preacher doesn't suggest we give up, he doesn't advocate suicide. He says we'd be better dead or not having lived, but if we live then there is something to do. We can bail from the game of climbing higher and higher, all this straining and searching gets us no where.
Instead we can adopt contentment with our lot. We don't have to buy the lie that we must keep climbing. Less and little and obscurity is fine.
Then we can receive everything as a grace from God to be enjoyed (three times in 5:18,19,20). This is the way to win over the vanity - by self-forgetfulness brought about by grace-fueled joy in life. That doesn't remove the frustration and make everything wonderful but in the years that we are given to live, with the stuff that we have, it's some relief. Man can stop climbing, grace comes down - and we see that there is someone more and better...