Why is it that many native English speakers can't write properly?

Even educated ones make so many basic mistakes. At the same time, I see foreigners from all around the world who are perfectly fluent in English and at least 2-3 other languages (even in poor countries). How is it possible that developed countries such as USA, Canada, UK or Australia can't make people learn to write correctly?
Asked Aug 11, 2014
Edited Aug 11, 2014

TIP: If it's not your answer to this question, please click "Leave a Comment" button under the question to communicate with the question owner.