Prepare for loneliness. This is a rarely mentioned problem of entrepreneurship, and many new entrepreneurs aren’t prepared for it until it happens. Being an entrepreneur is incredibly lonely.Customers may try out the competition, partners may disappoint you, teammates may leave, and investors may reject you. Alibaba was rejected by over 30 venture capital firms, so if you get rejected, but you believe in what you’re building, then keep building. You will be working lots of hours, so you might not see your family as often as you would want. As they say, “You can have anything in life if you will sacrifice everything else for it.” No mission too difficult, no sacrifice too great.