- Tail queries, which may seem unimportant on a case-by-case basis, but in aggregate could add up to almost half of your total queries
- Presentation, including the use of quality images, descriptive titles and price consistency
- Not everyone is shopping; customers could be searching for business information, and your search should be designed to handle those requests
- Irrelevant results, which can be hard to identify, but very frustrating for customers
- Mobile search, which is different from searches entered on desktops