仕事がたくさんあるが、明日までにできることはできる。でも、ミスが出ないか心配だ。


仕事がたくさんあるが、明日までにできることはできる。でも、ミスが出ないか心配だ。

I do not get the part that says ミスが出ないか心配だ Does that not mean that I am scared
of NOT making a mistake, 2 negatives = a positive meaning no mistake?

What would be the difference if it said this instead: ミスが出るか心配だ?




(According to a few mins' reflection) In 'Xか心配だ', X is what you want to
happen. So in the case of the example, ミスが出ない is almost always what you want,
and 'ミスが出るか心配だ' sounds odd.

As another example, you may or may not want some rain. If you're going on a
picnic, you say '雨が降らないか心配だ'. If you are a farmer and there has been no rain
for days, then '雨が降るか心配だ'.

* * *

'X **かと** 心配だ' is similar but the above does not (strictly?) apply.
'ミスが出るかと心配だった' sounds quite normal to me, as well as 'ミスが出ないかと心配だった'. (The
present tense 'ミスが出るかと心配だ' still sounds slightly odd; Tense doesn't change the
acceptability in ' **か** 心配だ'.)

**[Edit]** Both ミスが{出る/出ない}か心配だった mean _I was afraid there would be mistakes_.
ミスが出るかと心配だった sounds that mistakes were 'close' (but did not happen). For
example, if you are watching figure skating and the skating is somewhat
unstable, then ミスが出るかと心配だった fits better. ミスが出ないか(と)心配だった sound more neutral
with regards to the 'closeness'.

* * *

There are somewhat [similar](https://forum.wordreference.com/threads/fr-
craindre-avoir-peur-que-ne-expl%C3%A9tif.198124/)
[things](https://ja.wikipedia.org/wiki/%E8%99%9A%E8%BE%9E#%E8%99%9A%E8%BE%9E%E3%81%AE_ne)
in French.

