The product summary for my new electric shaver stand declares:

Select cleaning intensity to keep for optimal performance every day.

Ok, so do I have to select the cleaning intensity? Or does the stand select the cleaning intensity?

I thought I did, so I spent a while searching how I should select the cleaning intensity. Upon reading multiple product manuals, it turns out the stand does.

To clarify subject-less descriptions, you should use third person singular simple present:

Selects cleaning intensity…

or better yet, you should include a clear subject:

The stand selects cleaning intensity…

This applies to me most in code comments, for example:

// Add metadata

// Adds metadata