Self-employment is choosing to work 80-100 hours a week when needed instead of 40. It's not waking up and calling in sick to go to the beach. If you are not actively working you are usually not bringing in income. Even if you already have things set up to sell if you choose to not be active they will run out. The only “magic pill” is if you are able to find a way to add commercial value constantly to your product, and have customers already lined up. Some people are really good at that and can sell air at a premium when it’s already free.
Most people are just not cut out for it. They like to think they don’t require a boss or a company structure with deadlines. Not everyone is good at time management, finding a commercial use or adding commercial value, talking with customers, resolving customer complaints, troubleshooting technology issues on their own. People often take short cuts thinking they are saving time or money for it to be the opposite. At the end of the day things just take time and move slower then you like. Most are unwilling to put in the required time.
RE: The Value of Consistency and Perseverance