It Takes Two to Tango
The first rule of agility is ensuring that your team is flexible and can respond to customer behavior and quickly adjust strategies.
For employees of the customer's companies, your B2B portal would be a part of their workplace, so purchases should be convenient. Of course, if you offer specific niche products at an attractive price, there are only a few alternatives for buyers. Ideally, these employees will want to use the company site. With great reluctance, they may continue to use it even with a poor user interface or user experience (UI/UX). However, the latter will make them more likely to lean toward offline purchases or even leave the site for other suppliers.
Mind the usability of a B2B portal as a separate discipline of UI/UX in which the correct arrangement of interface elements should be combined with support for specific B2B logics and functionality.
Consider this win-win approach for customers and your goals as essentials for the success of your B2B ecommerce strategy.