Outsystems wraps most inputs in a span, as you can see in the screenshots below.

In some cases, that leads to cumbersome CSS selectors. For example, when I want to style a label succeeding an input, I need to write the following CSS: 

span:has(> .checkbox) + label {

... css styling

}

If I wouldn't be wrapped, I could just simply use the input + label selector.

Also leads to a cleaner DOM imho.