The butterfly effect is conceptually useful beyond just time travel stories and choice-based games. Though let’s focus on that specifically.
The butterfly effect simply states that the consequences of actions are sometimes difficult to predict and, consequently, any change to an action in the past can have far-reaching consequences. This is usually up to the point of being unpredictable.
However: just because the butterfly effect can become unpredictable doesn’t mean that it can’t be understood with the benefit of hindsight. While foresight is sometimes (and often) impossible, the same can’t be said for the opposite. A good implementation of the butterfly effect is one in which the order of events can be reconstructed backwards from the eventual result.
A good example of the butterfly effect would be Until Dawn. Many of the choices you make can have far-reaching consequences that are often difficult or impossible to predictA), the order of events is actually incredibly clear with the benefit of hindsight.
A bad example of the butterfly effect would be Season 3 Episode 26 of Lucifer (“Once Upon a Time”). This episode depicts an alternate universe where Chloe’s father isn’t murdered and, consequently, where she and Lucifer don’t meet when they were ‘supposed’ to. The reason this is a bad example is because many of the consequences have no clear “line of succession” from the initial divergence point (Chloe’s father dying/not dying) – sans Chloe/Lucifer not meeting when they were supposed to and then meeting in that episode.
Another bad one would be Harry Potter and the Methods of Rationality which is based on the premise “what if Harry Potter was raised by scientists?” but is, in fact, a complete re-write of Harry Potter.
The bad example is what happens when a writer uses the butterfly effect to lazily handwave changes that don’t actually fit with the point of divergence they tend to pick.
Though I mentioned that it can be useful beyond alternate history/time travel/choice games I’m not actually sure how.