The premise states two options that may be true when in reality there are other options that could occur.
For Example:
You need to go to the party with me, otherwise, you will just be bored at home.
Many times in a false dichotomy, the author will steer you in one direction leaving a poor alternative. In this case, you can have fun at the party or be bored at home. However, we know that there are other alternatives available. Perhaps you could go out for ice cream and later read a book.