Imagine you walk into a business and ask what they do. The receptionist asks for you name, e-mail, phone number, and birth date before she will agree to answer. Would you surrender your personal info, or walk away?
This is what many apps and websites are doing. You start the app or go to a URL, and you are presented with a log-in prompt, or connect with Facebook, or connect with Twitter, etc. This isn’t so bad if you can skip the prompt and try first, but more often than not, a log-in is required before the app/site will do anything at all.
Stop doing this, developers. You must allow users to try first, to explore, and to see for themselves what you can (or can’t) do for them.