All answers above are excellent, but are technical. Using the security management as point of view, think about the information that you are protecting.
If NO authentication is required to read that information (in a public or private point of view), that means that you aren't interested in protecting it.
If is an office, more than one people have access to it, there are several security considerations that the office maybe don't even consider (firewall, no password/wep protected wifi, anyone can plug a device on the network), that means that you rely on a third party about the access of this piece of information.
Now you have to do the calculations, how much it will cost if this information goes to the wrong hands ? That worth users being able to access it without password ?
Let's create two scenarios:
- This is an internal list of foods that the internal restaurant prepares aka menu.
- This is a list of customers with their credit card data.
Obviously those two scenarios are extreme, each one in this own way. But the fight of usability vs security will last forever. I once received a request like "let the user log in, even if the password isn't correct, but almost correct". That because some CEO, who can't type his password right, get angry when the application reject this login attempt.
Make an analysis of all risks, costs, pro/cons, you don't have to accept them, if you think that it's too risky, bring that to your CEO/CISO, and let him decide for you, than there will be no blood on your hands when something bad happens. Plus, they usually have a different point of view and importance about the business.