Hi, Christian. Thank you for your thoughtful comments :)
I appreciate your opinion, but the 80/20 rule doesn't work that way, it *matters* whether the number is 80/20, 70/30 or 60/40. You said that "the meaning behind it is, success comes from only a few activities,"--that I totally agree, but then why put the 80/20 number as a *rule* in the first place? The point of this article is exactly that--to criticize the 80/20 number.
Of course, it doesn't mean that the Pareto principle doesn't work at all. It depends on so many things. But as I said in the article, the "80/20" rule is just not true based on data, and using it may be detrimental for business. If we, individually, wish to use it as a rule of thumb, we must be very careful and considerate. It works for some, and doesn't work for some. Hence, if it doesn't work in general, can it still be said as a rule of thumb? I don't think so :)