Raise your hand if you have set up SharePoint using one account. Now, keep your hand up if it was this the “ADMINISTRATOR” account? Wow! I am having trouble typing now as I count the hands and try to type with the hand that is not raised up. In other words, I have been guilty of this.
Here are 2 links to some excellent resources on TechNet to help you be able to follow best practices with accounts on your next deployment.