Why is my adsense earnings different them my youtube earnings?

[David]

I have a youtube channel its very small and I earn very little but it shows that i make even less on adsense then youtube. For example its says i made a life time total of 40$ on youtube and i know you need 100$ to get paid so i didnt go on adsense for a while and i went on today and it said I had a total earnings of 3 dollars in my life time!What do you think is wrong i remember checking 2 months ago on adsense and it said 9$ and that also matched my youtube earnings. But I didnt take any money out because i know you need 100$ to get it.

[Nikola]

Odd

[Abbe]

sometimes money is added after ads clicked but later investigation shows that click was not validated or you used some illegal ways to get those clicks. You can ask the google by the way, though they don't bother to tell you the reason. Last year they just grasped my few bucks without telling me the reason.