I took two years ago a nice click that worth $ 5 from a biblical discussion website. That was a beautiful and exciting moment for me. The site has disappeared meanwhile but memories left.
I thought: So I can!
But since then the story is not repeated. In general, if I take $ 1 for one click I can consider myself very lucky.
I’m sure many people would agree with that. Provided you go about it in the right way, selling ads directly will nearly always yield more revenue than AdSense can generate.
But you’ve got to weigh that against the effort needed to sell the ads, format them for your page, deal with the contractual issues, invoice the customer, and collect payment. You have none of those hassles with AdSense.