As a customer, I often pay attention to such nuances as website optimization, page loading speed, awareness of different promotions and discounts, choice of delivery options, accurate pricing and all that. These are the things that increase my trust and favor with the online store.
About the shipping and accurate cost, these are very true and important comments and observations. When a customer can quickly and independently calculate the cost, which can now be done with the help of magento 2 shipping calculator by Amasty specialists, most likely they won't even notice it, but they will still have a pleasant experience with your online store.