A password ticket is a system-generated email that takes the user to a page on the site where they can set their own password. This is safer than some of the alternatives, and can help reduce the workload of adding large numbers of new users.
Adding the same default password for each user is not a good idea from a security perspective. Assigning each user one a different password is a lot of work, and you don't want to send passwords via email. What you can do is have TeamForge enable each new user to set their own password when they join the site.
This works the same way as the "Forgot your password?" functionality, but for new users instead of existing users.
The password ticket generated remains valid until one of these things happens: