There are many elements that make up a good anime - animation, art, character development, setting, theme... the list goes on. One of the most important elements is the plot, or the events that occur within the story. While no anime is complete without each element in place, plot is crucial. A show that isn't beautifully animated can still be well-loved if the plot is top-notch, but a pretty show with no substance will often be swiftly forgotten.
The best anime plots can be about anything, from an old man's career as a storyteller to a journey to the bottom of a mysterious abyss. To make an anime with a good story, no particular events are needed. Instead, the plot must stay compelling from start to finish - viewers need to care about what happens next. The plot also needs to be clever or surprising without seeming forced. If it's complex, it needs to be able to balance all elements without forgetting them, and if it's simple, it needs to find a way to stay engaging.
It's not easy to create a truly excellent plot, but these anime get the job done.