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The .flush() method can be used in place of .go() to kick off an animation you’ve built. It’s handy if you’d like to type out some one-off content that’s unknown until runtime. For example, you begin with a pre-defined animation (using .go()), and then wait to accept some user input before typing some more.
Animations executed via .flush() are forgotten upon execution, so calling .reset().go() later on will not type them out again. Additionally, since its intended to be used for more emphemeral content, .flush() will not execute the afterComplete callback.
For more information, check out the docs.