Have you ever heard of The 80/20 Rule (also know as Pareto principle) ? I think it is the fundamental to every business person or even to every human being. According to Wikipedia, this is how it defines The 80/20 Rule:
The Pareto principle (also known as the 80-20 rule,[1] the law of the vital few, and the principle of factor sparsity) states that, for many events, roughly 80% of the effects come from 20% of the causes.
One of the famous example you may have heard before are 20% of people in this world are having 80% of the wealth in the world and also 80% of your sales come from 20% of your clients.
The 80/20 rule is actually affecting our life and maybe we just not aware of it. Yaro from the Entrepreneurs-Journey.com explains in detailed how the 80/20 rule will change human life.
It is not statistically, exactly (but quite near to) 80% of the effects come form 20% of the causes but it is just a concept where MOST of the effects come from the LEAST of the causes.
When it comes to the Google Adsense earning for my websites, the Pareto principle is quite true. My websites that generate the LEAST traffics are contributing the most Google Adsense earning.
Maybe I should say this in another way: 80% of my Google Adsense earnings are the results from 20% of my hard works.
I do not know how is this happen. Maybe only one or two of my websites are having the niche and profitable topics.
Is the 80/20 rule changing your life too?
For AdSense, keyword price rate is the main factor that affect the earning. Lot of low pay rate keywords are useless. So better write article for those high pay keywords.