What is the main factor to keep a business alive?

There are many important things in a business, but what keep the business alive is the customer. No doubt that the customer is the main factor to keep your business alive. A business become a business in the first place because it has transaction between buyer and seller. Steve Schneider once said "You can have the best product in the world, but if you can't market it, it is not going to matter to anyone but yourself.'' It is obvious then, even if your company have a graduate from the top university in the world, or have all the funding in the world, have a great mindset for building a business, having the best location for your business, the greatest products, and the most motivated and well trained staff, and you can be an amazing salesman but without those product being delivered to your customer, then your business in nothing. On the other hand, if you are having a great customer base then you also have a lot more business opportunity than you could ever do on your own. So, if you are good at marketing your business and you have a great base of loyal customers, people who know and trust you, people who are now your friends, people who you have developed a great professional relationship with over time, who are already doing business with you, and who are already sold on the job you are doing for them, you have a tremendous sales force for your business. So if your customers are your most important and priceless business asset, knowing how to cost-effectively attract them in large numbers, then profitably convert them into loyal, renewing or repurchasing customers who will not hesitate in referring others to you, is the most important business skill you can possess.