Its true that many people still do earn well with adsense but because now there is too much competition, so its becoming difficult day by day
This is true. Ive been at it myself for some time and its really hard work. I get burned out fast. DP for a break
You have to work hard to success in Google Adsense. If you have a blog you have to write unique and valuable content. And do some SEO. Thats all. You can gain your key with Adsense.
So far AdSense isn't profitable for me. But I convince myself that I need to work harder to get what I want. I believe in AdSense is good way to earn passive income. I think it is also true to everybody who work with Adsense.