Why log in once when you can log in twice? Two-factor authentication can give you some added protection, and it's fairly easy to set up.
A security breach at Adobe earlier in October will impact at least 38 million users, according to Krebs on Security—and that number could grow because a recent file dump of usernames and hashed passwords taken from Adobe.
Don doesn't need to keep other people off his PC. He asked me how he could skip the logon screen and boot directly into Windows without a password.