Noindex URL has incoming hreflang
This means that the URL in question is defined as a hreflang alternate, yet is noindex.
Why is this important?
Hreflang tags are interpreted by search engines as indexing instructions. An English page that has hreflang pointing at its French alternate is instructing search engines to index both the English version and the French version, and to consider each as equivalent in their respective languages.
If this English page also had a meta noindex on it, then this would be an instruction to not index the English page.
So the hreflang is saying 'please index the English page', and the noindex is saying 'don't index the English page.'
This type of conflicting instruction serves to confuse search engines, to the point where they may ignore the hreflang completely.
What does the Hint check?
This Hint will trigger for any URL which is defined as a hreflang alternate, yet is also noindex.
Note: This Hint is very similar to another Hint: Has outgoing hreflang annotations to noindex URLs. The difference being that this Hint is analysing the target page of a hreflang annotation (i.e. incoming hreflang) whereas the other Hint is analysing the page with hreflang on (i.e. outgoing hreflang).
Examples that trigger this Hint:
Consider the URL: https://example.com/us/page-a/
The Hint would trigger for this URL if it had a noindex in the <head>:
or in the HTTP header:
and if the URL is listed as an hreflang alternate, either on another page, or on the page itself via a self-referencing hreflang;
How do you resolve this issue?
This Hint is marked 'Critical' as it represents a fundamentally breaking issue, which may have a serious adverse impact upon organic search traffic. It is strongly recommended that Critical issues are dealt with as a matter of high priority.
There is a clear conflict between hreflang and noindex. Assuming that the hreflang itself has been set up correctly (i.e. it is pointing at the correct URLs), then the solution is simply to remove the noindex from all hreflang URLs.