After all the installation steps are completed, the user is asked to configure the website. Installation script would ask for website name, email address, administration account information, regional settings and if you want to subscribe for update notifications or not. All of these settings can be changed later on as well.
Please note that update notifications will only work if you have SMTP configured for your website. In simple terms the ability of system to send email should be there for updates to be sent on your configured website Email ID.
Don't be lazy here with the password and then later on blame CMS security.