good customer service keeps customers happy and return to buy more products which keep money coming into the business
research and development
research products that there are not a lot of on the market this will then catch customers eye as a new product and price of it will be up to the business
finances
sales and marketing
make sure sales are coming in at prices which maybe cheaper if your product is popular this will increase sales
marketing make sure you are competing with businesses around you
production
make sure products are up to scratch with no problems to keep customers happy