Mark's co-author, Andrew, here. I just published a really length reply above, so hopefully that answers your question. In a nutshell, just like in business the biggest secret sauce is hard work and consistency - it's not like we're giving away the keys to the treasury where they print money!

With that being said, there are a lot of nuances to picking a good niche (especially in drop shipping where the competition can be fierce and margins low) and to operating a drop shipping business (as it can get logistically complex). Those are some of the things we're trying to shed more light on in the guide.