For me, it seem difficult in the beginning to get traffic and click. Today, the learning curve effect happen, practice makes perfect,get more experienced and become more efficient to get traffic and more click.
Maybe just to share. There is one point where my Adsense revenue increases tremendously after the site took over the 5th position of a popular keyword from several pages down..
A few of my recent sites I put a lot of effort into sort of peeter out around 500 per day. Is that good? I guess not Eric