From the customer perspectives, what you want to study is what motivate the customers and drive their satisfaction so that they can buy again from you. Finding the answers will point you to the right direction.
The responses will be intriguing and will definitely address the concerns of marketers. Sir I would like to suggest that studying, whether satisfaction eventually lead to loyalty will add more indepth understanding to the overall problem statement.
There could be n number of perspectives. The most important is navigation and search keyword. eCommerce portal should be efficient enough to navigate all the desired products that customer is requested to buy and then navigating customer based on that search key is another important aspect. i would recommend to focus more on keywords. For example, a customer will not type difficult keywords, customer always want to put in easy keywords in search box and he/she expects that portal would come up with search results. a keyword like "cheap mobile". You can explore more on keyword "cheap" and then try to look up dictionary for synonyms of word "cheap" and related all products not only to word "cheap" but also synonym words.