The person in the comments merely noted that it doesn't work well in Vietnam. Given that this is the internet, and given that the author said it works well with

The person in the comments merely noted that it doesn't work well in Vietnam. Given that this is the internet, and given that the author said it works well without giving a clear location as to where it works well, I think it's safe to say that in this specific instance, "Why did you expect it to work for every single place on the world?" has a simple answer: Because OP said so, in the article. Nobody here demands that an OSS project works well in every part of the world. What is being criticized here is the US-centric view of the article author, and the original comment merely noted that you can't make a general assumption of suckiness based on one location. Again, the problem isn't with the app. It's with the way the article assumes everyone reading this lives somewhere where the app doesn't suck.