I´m sure thats the way to success. For different reasons. If you are an affiliate, a one man show or with some freelancer in background, you are extremely limited in resources like time, men power and money. You have to finish a lot of jobs. Your have a knowledge about lot of things. But probably you are not really a Pro in more then one. A bit
SEO, a bit content marketing, a bit social marketing, some basic coding skills. But not able to beat a professional of one of this services.
But if you take some (more) money and if you have a plan, leading skills and time, if you hire professionals for all services you need, for sure you will rule the targeted serps and niches sooner or later.