Why doesn't the default "off topic" close reason appear when you add a custom close reason?

Question

I've added the following close reason to three of the four meta sites where I moderate:

The problem described here can no longer be reproduced. Changes to the system or to the circumstances affecting the asker have rendered it obsolete. If you encounter a similar problem, please post a new question.

However, this appears to have deactivated the default close reason:

This question does not appear to be about $Topic within the scope defined in the [meta-help].

Where $Topic gets replaced by the site name and [meta-help] is the relevant link. This is rather unfortunate as this is a rather useful close reason to have on a child meta. I've also noticed that we've got the same situation on the DIY main site. We've got two custom close reasons, but the default has gone missing there.

Now on the "manage close reasons" page it states, above this reason:

Shown when no 2 off-topic reasons match on a closed question.

What does this actually mean? Is this just designed to appear on the closed question if there wasn't agreement on the reasons chosen?

What can I do to get this close reason back (other than deactivate the one I added)?

Unfortunately I can't check to see how things are set up here (where there are three custom close reasons) to see if I've missed anything.

I'd like to know before I go messing with the Meta Stack Overflow close reasons.

Answer 1

The way to get the reason back, while preserving the custom reason, is to add the default reason (or something resembling it) as another custom reason too.

The default reason shows also up when people close as off-topic/other.

I ran into the same issue on the site I moderate and was surprised then; my first impulse was to add the reason back (as described above). But I am now of the opinion it is better (at least for moderately sized sites) to only have specific custom reasons and to do everything else with "other," where one is pushed a bit to explain via a comment.

Put differently, a catch-all off-topic thing exists anyway it is "other" (with some added explanation on a case by case basis).