Difference between 'expiration date' and 'Password expiration date'?

[Ken Hornstein]

>I was looking deeper into kadmin, and saw that there is an
>'Expiration date: [never]' and 'Password expiration date: [none]'
>in every principal... What's the difference?
>
>If I dare a guess, the first expires the whole principal (including
>password) and the last only expires the password... ?
>
>If I'm right, why would I want to expire the whole principal!?

You're right.  I don't think most people would expire principals, but I
could think of a few reasons.  For example, if you charged for accounts, you
might tie the expiration date to when the money for the account ran out.

--Ken