If you own a small business, you have to provide them not just for yourself but also for your employees. Then add variations in cash-flow to the equation. Don't make the decision to start a business all by yourself. Talk it over with many people, and listen carefully to their responses. Seek out criticism.
Successful entrepreneurs take only calculated risks.
They have a mix of optimism and realism. Listen to your family and friends. Listen to professionals who know you. Talk to potential competitors. Talk to experience businesspeople.