JSFiddle - React, Tailwind, and code Playground

HTML

<div>
    <input data-bind="value: work"/>
    <span data-bind="text: work"></span>
</div>
<!-- ko foreach: nowork -->
<div>
    <input data-bind="value: $root.nowork[$index()]"/>
    <span data-bind="text: $data"></span>
</div>
<!-- /ko -->

JavaScript

function vm() {
    this.work = ko.observable('Change me and span changes'), 
    this.nowork = [ko.observable("Change me and span doesn't update")];   
}

ko.applyBindings(new vm());