I don't really think it matters. if you've been cruising with carnival for any amount of time, they know what cat you're getting. For awhile, I was only interested in balconies.. now, they know I will spulrge on a suite. So, they get me offers for suites.
As you progress through life, you hit certain points where your income has grown. So, your vacation dollars will grow. Carnival wants your vacation dollars and will try and target them.