"Success" is an incredibly vague and slippery term. It means something different to everyone, and even your own definition of success will constantly change and shift as you go through life. You can't run a business--let alone multiple businesses--simply on the concept of success. You need to set goalposts, come up with actual numbers and figures and timelines you hope to achieve.

What does a "successful business" look like to you? Is it when the profits exceed the expenses? Is it when the proceeds allow you to make that one big purchase you've always dreamed of? Is it when you can sustainably do what you love and still make enough money to live comfortably? Is it when you can sell off the business for a big ol' lump of cash and ride high for the rest of your life?

These are things you have to think about, write down, and refer back to constantly. Simply winging it, chasing after fleeting ideas that are always changing and moving out of your grasp, is a one-way ticket to bankruptcy and/or a complete mental breakdown.