Why Does Outlook automatically log me in without my email address and password?

Your computer (or device) is being saved as a "trusted device". If you prefer to be prompted to sign in with a password, you need to go into your outlook settings for security and privacy; close to the bottom of the page will be an option to remove all trusted devices. Any device listed as a trusted device will negate the sign-in process. If you need more of an explanation, go to my previous post from this thread on September 17th, 2015, and it will have a longer step-by-step process for removing trusted devices.

I never tick the box "Keep me signed in" and I have signed out but it still automatically goes to my email.

Not good enough Microsoft!!!!!

I am having the exact same trouble.  Only since Hotmail switched to Outlook.

Try my September 17th entry, 2015. I had this happen to me with my new computer using Windows 10. I found out it would continue to sign me in even after restarting the computer because now when you register and first use a new computer with Windows 10 on it, it will default your account to the "trusted devices" and nullify the password requirement. If you follow my steps in my September post on the 6th page of these replies to the original question, it will tell you how to remove trusted devices from your account, therefore requiring a password every time you go to log in. I find it absurd that if my device is trusted that anyone can turn it on and access everything accept changing settings. They could make, delete, or copy emails, find other email addresses from the security features, let alone access everything on the hard drive that isn't hidden or password protected. Why anyone would trust a device hooked-up to the Internet, I will never understand.