Top level domain transfers fail for a number of reasons. Some of the most common reasons are:

1] Domain name is within 60 days of initial registration

2] Domain name is within 60 days of a previous transfer

3] Domain name is in "Lock" status (e.g. Registrar-Lock or Registry-Lock)

4] Domain Name is in 30 day Redemption Grace Period

5] Administrative contact email address is out of date

6] Administrative contact fails to confirm transfer authorization or denies the transfer request

7] Existing registrar denies the transfer for legitimate reason (see below)