So I was approached by a video ad network. I rarely try anyone new but they looked interesting. Put the ads on, and they are in Italian (neither my site or audience are Italian). Can't change the ads. I write to support twice. No response. I write to the gal who originally contacted me, and the email bounces back. Twice.
I approach a reputable company about advertising. We negotiate and go back and forth for about a month. Email, phone, etc. I finally tell them I am ready to commit, and they stop communicating. Just stop. No explanation. Nothing.
Say what you will about Adsense, but at least they are there. They are not flaky. They are generally professional. They always pay on time. That really does count for something these days.