- I want to be able to explore some of the functionality without providing any information at all. I want to read some copy, see a demo, see some screenshots, and ideally play with some functionality.
- I have no trouble creating a username/ password to try out a site. I have a 'throwaway' username/ password combo that I often use for sites I am just checking out.
- I will almost never use one of my established social identities for an app that I have just heard about, or one that has no traction yet. I don't want brand new apps to have any connection to my established identities, unless I have really good reason to trust that app and its developers.
Hope that helps, I imagine this is a pretty common mindset when people are checking out new apps.