☐ Coincidences to get characters into trouble are great; coincidences to get them out of it are cheating.
Authors of yore used to employ coincidence all the time. Since many writers are well versed in Dickens and other classics, we sometimes try to use those same ploys. But the coincidence trick is much harder to get away with now. This advice from filmmaker Emma Coats, a former Pixar staffer, puts it in perspective.
(The Pixar “Rules,” by the way, are pieces of advice rather than rules, as is true with many of the things writers are told. For a deeper look at them, grab the free e-book Pixar’s 22 Rules of Story Analyzed by Stephan Vladimir Bugaj, another former Pixarian.)
Yes, coincidences happen in real life. But in story, unless they cause trouble, they are unsatisfying for readers. That’s because fictional coincidences are usually pretty obvious cases of authorial manipulation. What really makes for engaging stories is stuff that characters do intentionally. If random, implausible stuff just happens to your protagonists, it not only makes the story feel contrived, it makes the characters seem passive.
Make your characters proactive. Their choices and actions will make for more engaging story material than stuff that happens accidentally. Especially if the likelihood of the “random” happenstance the author has orchestrated is vanishingly small.
If your first draft relies on coincidences, consider whether they can be replaced by direct character action. If not, try to make them more plausible. Or more disastrous. Or both.