Just as everything that goes up must come down, every action must have a consequence. Whether the bad decision you make is big or small, the outcome that follows can be absolutely life-altering.
We don't have the power to see the future, and so what seems to us at the time like a tiny thing or maybe even the correct decision to make can, in hindsight, be the cause of our downfall. Or even maybe the downfall of all of humanity.
It is the unfortunate nature of life that one person's bad move can impact many others, in the case of lots of apocalyptic films we see this concept tried to its fullest extent.
You can unleash literal hell, you can poison the world with a deadly disease, you can cause the deaths not just of your family but of everyone else's too. Imagine being that guy, eh? That's got to feel bad.
If you ever find yourself worrying that you've made the wrong call on an important decision in your life, rest assured that at least you haven't messed up as badly as these guys.
10. Gambling With The Future - Back To The Future Part II
Someone always just has to try being the wise guy, don't they?
When Marty McFly makes the decision to buy a sports almanac and bet on races he knows the outcome of, he most certainly didn’t expect that it would end up making his mum marry the absolute beast that is Biff, and that it would make Biff the Donald Trump of the alternate future.
After getting hold of the almanac, Marty and Doc carelessly allow it to fall into Biff’s hands. Whilst they’re away dealing with their messes, Biff borrows the DeLorean and travels back in time, giving his younger self the almanac so that he can get rich off betting.
Because of this, when Marty and Doc return to 1985 they find that Biff has become incredibly rich and is now Marty’s stepdad!
Had Marty heeded Doc’s advice and made the sensible decision to return the almanac and not mess with time-travel, none of that would’ve happened.