I don't understand what's insightful or new with this article. Advertising is basically an arbitrage operation. To do it right one needs to look at the conversi

I don't understand what's insightful or new with this article. Advertising is basically an arbitrage operation. To do it right one needs to look at the conversion funnel, figure out the ARPU for different advertising channels, prune campaigns that are not effective and invest in ones that are. If you are not doing that then of course you will get burned, everyone who is thinking about making an ad spend knows this or should be able to figure it out.