Some people cannot speak English? Is it due to social, economic, or poor schooling conditions? Does the fact of not being able to speak English have any impact on someone's life?
Actually, everyone 'can' speak English, unless they're dummies.
People who cannot speak English cannot do so primarily because they did not have the opportunity or necessity to use this language in the same way as people of some other countries had. The best way to learn a language is to use it in the natural conditions, an opportunity that some people did not have. It is as simple as that. However, when we come to the matter of pronunciation, the matter is not that much easy.
The people that cannot speak English its just because they don’t like the language. Some friends of mine always say that English its very hard to learn, and I always say to them. Its hard to you because you don’t like it, because if you like English you will learn very fast.
I do believe we can do anything we really want.
So, if there are people who can't speak is just because they don't want to.
I don't believe there is logical and predictable link between this fact and money, family or anything else. I know lot's of rich people who just don't care about it and don't speak any English at all. In addition to this, I know people who learnt English, no matter their economical situation.
Humanly speaking everybody can speak English, the point is that several people find it easier to study than others but it doesn´t mean they´ll never speak this language.
There are things in our lives we can do easily, and other things we have a hard time trying to learn, and there´s no difference when it comes to learning English or any other language.