It's very simple to unlock a domain and re-lock if you need to do a nameserver change, or in the event you really do want to change registrars.
There have been a lot of domain hijackings lately, and domain lock is a simple tool to help prevent them. Making sure your administrative email is valid at all times is very important too. You should also make sure you only use strong passwords (10+ characters, mixture of upper and lower case, and including digits and letters) for your email and your domain management.
