Generally, they&#x27;re not replacing UIs, they&#x27;re replacing call centers. The idea is to put an NLP and task layer between the user and a call center agent, with the hope that you can automate commonly-recurring tasks and save opex. (I call them &quot;opportunistic interfaces&quot; -- situations where users are unable or unlikely to use a formal web or app UI, so you&#x27;ve got to stick with something that works over a phone or SMS.)<p>In this case, they&#x27;re probably talking about the blue-collar labor force for sick-day management, so you need a lowest-common-denominator interface; you can&#x27;t assume they have smartphones or even Internet service, so good old fashioned voice or SMS is your best choice.