I don't think so. Because I might be good at doing the task, but not as good as hiring and managing someone else doing the task and if the quality of the job done by a third party is questionable, you won't be able to raise your price or even selling to the same customer anymore. I don't think it is a black and white decision. Instead I decide to hire someone to do the tasks I can't do, either because of lack of skills or lack of time/resources.