The success any business enjoys is entirely dependent on the decisions made by the owners and managers. If you make bad decisions, how can you expect anything but a bad result? If, on the other hand, you make well thought out decisions that are backed by facts and data, you can be reasonably assured those decisions will result in success.
One area where decisions are especially critical is how you spend your money. Every business has a limited amount of resources and if they are wasted, the business will not survive. Many owners were motivated to start their business to get away from a formal corporate culture, but one thing common in large businesses can be put to good use by the little guys as well. Every owner should decide what level of spending needs a formal proposal, examination, and then approval before the money is spent. This should include any type of financing as well.
This does not mean you need to let someone else make these decisions for you, although it would be valuable to run any large decision by your accountant or attorney for their opinion. It does mean, however, that every decision will be based in reality and on concrete data with a plan on exactly what to do. Even if every step is only completed by the owner, this is still an invaluable way to preserve your capital and only use it where the return is most likely greatest.
Another mistake is to not make a decision when one is called for. For example, after every sale, do you contact your customer with additional offers they might be interested in? If you have not considered the question, the lack of a decision on your part is costing you money.
It is a fact it is easier to sell to someone who has already bought from you than someone who has not. One huge hurdle that every online business needs to get over is to convince the visitor that the seller will not rip them off. You have already gotten past this with your buyers so why not take advantage of this fact and offer them something else they may want to buy?