Imagine that you are in a foreign country where you don't speak the language. You're hungry and you need to ask someone on the street where to buy some food. You don’t have the words to say it, but you can probably rub your stomach and people will know where to point you.
If the app has sufficiently unique features or design, then encountering those will be like hearing words from a foreign language. If the features or design are familiar carryovers from other products that people are used to using, then they will make sense immediately. People start using an app with different prior skill levels, so it’s important to learn how much variability is present so you can improve.
In order for new users to experience a successful Adoption of an app with unfamiliar vocabulary, you need to first find a common language through which both the app and the user can communicate. Speak to the user with a shared vocabulary.
More often than not, that language is the user's goals. If you are able to show the user how the unfamiliar features relate to their goals, then those features will suddenly make much more sense. This is why The most successful app adoptions come from a project.