Anecdotal evidence upon advertising effectiveness

I am going to make a blanket observation that you can't make blanket observations about the effectiveness of online advertising.

There are some who will say that Facebook or Google advertising is worthwhile, while others will say that it is not.

The truth? It depends.

Take this one story, which was offered as a comment to a SoshiTech post. Excerpt:

If were spending 250$/month for ads and each lead is a minimum of $1500 conversion, if 4/5 leads failed then even one is already making profit!