I just wanted to share. I am sorry if this explanation unsatisfactory and the results will probably not be the same or different. Since this is based on my experience.
Do you have a website in English, but has too small CPC? just 0.05 or just 0. 2 per click? Though the site you build up already through keyword research with very super selective, and also the visitor from premium country but CPC still low. If so, maybe your site exposed to Smart Pricing.
Q: What is AdSense Smart Pricing?
A: For technical definition you can read here:
According to my experience, Smart Pricing is very annoying. Because the AdSense CPC will get very small, while visitors from premium countries: United States, United Kingdom, Canada and Australia.
Q: Which is affected by Smart Pricing, the Site or its AdSense account?
A: The AdSense account
Q: What will I do if my account exposed to Smart Pricing?
A: Remove your AdSense ads or increase CTR.
Smart Pricing is due to advertisements posted on not qualified site. The quality here is according to Google AdSense, not by you. Suppose you have a website and have a lot of articles, many visitors, but AdSense CTR is very small, less than 1% (or even no click at all), you should immediately remove the AdSense ads are posted on that site. Why? Because even though there are clicks, impressions logged on Google AdSense stats and adversely impact the performance of your AdSense account. Immediately remove the ads on your not qualified site. Or if you still wanna to put the ads on that site, you should be able to increase the CTR, for example, change the ad layout, colors, etc.
Addendum: According to some sources, Smart Pricing is common on sites with have visitor not coming from the Search Engines, for example, from social bookmarking, forums, FB, etc. Why? because the visitors who visits the site did not to look for a solution, but rather to the curiosity. Consequently google protect its Advertisers (google makes free the click to the Advertisers) who put up on your site so that's why the CPC is so small.
Q: If I already removed the ad, now what I have to do?
A: Just wait, Maybe in 30 days, then you will see results. (I myself, I get the results after 3 days I deleted ad on my site which is not qualified)
Q: Next question, Do i have to remove all the AdSense ads on my site?
A: Not so. You only need to remove the ads on your sites with have so poor CTR quality, for example, you have 10 sites. 8 of 10 sites have super small CTR. while the others two were good. Well just remove the adsense ads on your 8 sites, while the remaining leave it alone.
That's all I can share here. This is my experience and maybe the results are different for each person. Hopefully this articles can provide benefits to you all.