As content on the web becomes more personalized, just about every website asks you to create an account and log in for a better experience. You probably click on “Log in” links and buttons several times a day without much regard for their presentation. That means you might not see anything wrong with this picture:

Compilation of website screenshots showing buttons and links with Login and Logout

But there is something wrong with that picture: login is not a verb. A link or button that says “login” is like a search field with a submit button labelled “Terms” — it’s not an action.