"fickle world" is correct and usable in written English.
You can use it to refer to the unpredictability of situations or events, for example: "It's a fickle world; yesterday's successes can quickly be forgotten".
In the fickle world of dance music, trance has long been ridiculed.
On average, a model can only work for four years in the fickle world of fashion, he estimates.
But surely his steadfastness is proof of an old ideal: let the fickle world come to you.
And if it stumbles, as Mr Castellano must know, the fickle world of fashion will be merciless.
THE fickle world of fashion, from gilded to space age, has inspired fantasy images to pique the imagination.
Richard Li may no longer have a hot hand in the fickle world of Hong Kong commerce.
If we constructed a mythology for Appalachia, one of the most powerful and fickle world-makers in our pantheon would be the stranger with a camera.
The current mantra is "Move fast with stable infrastructure", which speaks to the organizational design challenge of operating at scale in a fickle and volatile world.
Investors would do well to focus on how 19-year-old Netflix has proven to be nimble and adaptive in the oh-so-fickle world of America's entertainment habits.
The notoriously fickle theater world trusted her too.
