Let's say it costs me a $100 to outsource the building of an Adsense site and the link building, there's a tiinny chance that this site will be a winner, in which case I recoup my costs for the other 10 sites I built that bombed.
There are also waaay to many moving parts and crap to juggle. You need to use a tool like ManageWP (awesome tool btw) just to keep organized.
Most of my microniche sites earn me an average of $50/month. Not bad you say...but my absolute WORST affiliate sites earn me that much with a fraction of the traffic, less work and no worries about a manual account review from Google. And the WINNERS among your affiliate sites simply BANK for you over and over.
However, I still do build authority sites that do well, just not feeling the microniche model any more.
Anybody else find juggling all the microniche parts, spreadsheets, etc. too daunting?