When you work as an entrepreneur, your biggest enemy is yourself. That is because responsibility is bigger than being an employee. Many processes and decisions put their weight on you and as a result of that, a bad decision of yours may change the whole financial and market picture of your company.
The key to handle this responsibility is to never stop. Take as fore-granted that mistakes will be made and continue working on finding new solutions for them. Evolve and mature your ideas and NEVER quit.