You don’t like my blog? No problem, it’s not for you.
If it were, you would like it. At least some parts of it.
Seth Godin writes in one of his books that the spelling errors in Nigerian email scams serve a purpose. They filter out the smarter, arguably more difficult, readers. If you are put off by the spelling and the grammar you won’t reply to the email. Good, they don’t want you to. Because you most probably will be wasting their time. Others will be better victims. The Nigerian Prince email is not for you. 
And so it is with everything else.
Liberating, isn’t it? Suddenly we don’t need to make everyone happy with our art and our product. We can’t make everyone happy anyway, because different people have different preferences. But now we don’t have to feel so bad about it.
Another example: You approached a girl on the bus? And she rejected you harshley? That’s fine. You’re not for her.
Isn’t it useful to know that? To know it early?
 I doubt it’s always on purpose. I think some of that fraud spam is just 14 year old kids writing.
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