My mistake. I have closed this as notabug.

On Sat, 21 Dec 2019, 18:50 Eli Zaretskii, <eliz@gnu.org> wrote:
> From: Nikolaos Bezirgiannis <bezirg@gmail.com>
> Date: Sat, 21 Dec 2019 16:00:39 +0100
>
> I think there is a typo in the docstring of the `goto-line` function.
> I attach a fix.

Why did you think it was a typo?  What does (N - 1) does in Lisp?

Thanks.