[onion2k]

It has a chevron to indicate options when the input is focused as well as when the user hovers over it so there's no reliance on a mouse input. That seems to be enough to me. Why would the user need to see a chevron all the time, eg even when they're not interacting with the element?

[dublin]

It's needed when they're using a modern touchscreen computer instead of an ancient mouse-driven one, like I did when reading the link from this post this morning (Surface Pro undocked, so no keyboard). There is no clue the pull-down is even there otherwise!

[rovr138]

To know they can interact with it.

If the field is optional they might just skip it to not type.

Not everyone can hover over it.