From IRC:
[12:49] <aharoni> Hallo.
[12:49] <aharoni> https://en.wikipedia.org/wiki/Miss_Israel has an interlanguage link to Hebrew,
[12:49] <aharoni> but if I actually go to the article in Hebrew, then it doesn't have interlanguage links.
[12:50] <aharoni> If I'll purge the page, I'll probably see them, but shouldn't that be automatic?
[12:50] <sjoerddebruin> Yeah, but the cache is somewhat stronger in the last few weeks.

I encounter such things almost every day.

Nobody should have to purge pages manually to get the links to show up.