In a webmaster hangout on YouTube, Google’s John Mueller said that the search competition is different across different country domains:
[Some people think that if] they rank in one version of Google or one country domain, […] they should rank the same on all others or on .com, the US. And in general, that competition is very different across these country versions.
So that is something where it would be completely normal where we would have very different rankings in these different country versions. A site might be completely fine and good in rankings in Google Canada because there are fewer other sites that are competing for these queries on Google Canada.
But because the competition is so much stronger in the US, maybe it would be ranking very differently. So from that point of view it is kind of normal that you would see this difference. It is not something that I would call out as a bug on our side or a bug on your side, not something that you are doing something wrong.
You can view the video here:
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