Which are 3 most important challenges of retail industry?

Interesting question but this all depends on what part of the world you are in? - For the West I would say:1) Changing buying behaviour of Consumers.2) eCommerce / Internet3) Moving to Omnichannel Retailing If you are in the Middle East, I think the challenges are different:1) Sustaining footfall in the ever increasing number of malls2) Internet / eCommerce3) Retailing knowledge within Head Office

if you are talking about the retail industry in KSA ,I can say the most important challenges  is the new law of ministry of labor related to females work that you hand over retail stores for females who are so far of this environment  of  work in Saudia Arabia 

3 most important challenges of retail industry are: 1. Creating a good image and identity of your brand 2. Achieving ultimate customer satisfaction 3. Balancing between cost and profit margins of the business

New entries. Unusual low prices. changing markets roles.