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- get the registered clients into the system fast
- make unregistered users to register
- convert a visitor into a user
- provide a way to recover an account

In time, the priority of those things changes, ie: at the beginning of a startup you want more new users, the register process must be the first thing a visitor sees in the page, after a while and a solid client base you want those clients to login fast and without issues.

Let’s see some of Google’s login forms now:

Size of the font and spacing changed for better focus on the link.

Here come the blue buttons.  Call to action all the way. Unfortunately, I personally had problems logging in, I pressed the “new account” button instead of “login” multiple times.  Wasn’t very happy with those. The naming on the button changed a lot, “get started”, “pick a name” or simply “new account”

The next one is the one i can see today on my browser, it really doesn’t have a actual call-to-action button, just a size priority. It’s better.

Note: I’m more than sure it depends on the OS/BROWSER/GOOGLE SERVICE etc.