If for some reason your Outlook program keeps asking for your password, it's because Gmail isn't allowing Outlook to authenticate.

To fix:

• To fix this issue go to: www.gmail.com, and log in to your account. 
• In the upper right of the browser window, click on your profile picture.
• Select Manage your Google Account.
• On the next window select Security.
• Scroll down the screen until you see Less secure app access, click on it.
• Make sure Allow less secure apps = ON, if not toggle it ON. 

After completing the following steps your Outlook should now work.