I don’t think anybody chooses this, truthfully. Maybe he didn’t get the memo, or never had the chance.
Edit - had a thought, what if he was one of those 1,000+ Cubans who thought they would work as engineers in the Russian bases? They probably don’t speak any Russian and would have no idea.
This is the only semi-legitimate reason I can get behind. For kids in grade-school.
If anybody outside of grade-school brings this up, I would laugh and ignore.