Managing an e-commerce store should be the easier part of the process. Product details and prices need to be easily updated. Shipping and tax information has to be considered and applied to the right products, services, and customers. Customers should be able to make a purchase using an intuitive shopping cart. The payment process must be flexible to accommodate all the common payment workflows.
In short there are a lot of moving parts when it comes to e-commerce. If done right it will become a revenue channel for your business. If done incorrectly, it will cost your business money, time, and customers.