To be a successful entrepreneur (serial or standard), you need to cultivate certain key skills. These skills include:
Strong leadership skills, particularly if you plan to have many employees.
Good communication skills so you can market successfully and lead your companies to success.
Strong market understanding. You need to know what gaps currently exist in the market and how you can leverage them for profit.
A lot of drive. To succeed as an entrepreneur, you need to be willing to buckle down and do a lot of work, often working more than 12 hours day-to-day.