If your first film does badly, there's no guarantee of the second film.
Without properly functioning civil courts, there is no guarantee that innovative entrepreneurs can claim the rewards of their ideas.
In the racialized space of capitalist gentrification, police are not only arbiters of the peace, they are the muscle of retail racism: You can only be in this space if you transcend your blackness by showing us some green dollars. Even then, there is no guarantee that green will transcend your black skin.
That's the unpredictable part, and that's what worries every coach: Protect the football. That's why, when you go into a ballgame, you may be favored, but there's no guarantee you're going to win it.
More draconian forms of policing and punishment are no guarantee of a reduction in violent crime.
There's no guarantee, and there's no proper path to follow that will directly lead you to where you want to go, but stick with it. If you know in your bones that this is what you were put on this earth to do, and the world would be a darker place without you pursuing your dreams, then keep at it.
Even with good maps, there's no guarantee that the public will get the word about landslide hazards, or that state and local governments will take action to discourage or prevent building in dangerous areas.
One of my great regrets, and I don't have many, is that I spent too long putting people's status and reputation ahead of their more important qualities. I learned far too late in life that a long list of letters after someone's name is no guarantee of compassion, kindness, humour, all the far more relevant stuff.
There's this existential argument that comes in, at some point, when you're over-thinking the songwriting process. There's no guarantee that the more time you spend or the more you concentrate on certain aspects that that's going to produce a better result, especially in the arts.