Shipping concerns really break down into despatch and delivery . You need to have confidence the goods will turn up and you need to know they will arrive when you want them. It boils down to faith in the brand and many are more likely to shop from High St brand or established and respected e-tailers like Amazon. Internet companies should be able to turn around an order in a few days and though many do I'm still amazed to see '28 days for delivery' appear on sites. If you don't have it in stock or you can't source within a few days you should be selling it.
Delivery is somewhat more problematic at present.
Hopefully a solution can be reached and recent suggestions that bulky orders could get shipped your local post office for you to collect is hopefully a sign of some progress. I think once people take that leap of faith most of their fears will be allayed. That's true there will always be exceptions and perhaps more significantly many enjoy the social interaction of shopping. Online shopping should always be viewed as an alternative through either convenience or pricing.