Actually, it is pretty common practice to allow a user to change his/her own password. They should not, of course, be allowed to change any of the rights that come with their username. Certainly they should not be able to change other people's passwords. ("You buy lunch and I'll tell you what I changed your password to."

)
Some systems, including Windows Server and Novell, allow the administrator (SYS in Adagio terms), to set such things as:
- permission for user to change password,
- expiry of passwords (monthly, for example) or not,
- whether a previous password can be reused,
- minimum standards for passwords (legth, etc.).
Usually, even the administrator cannot read the user's password, but can reset or change it.