Deleting files sometimes takes a very long time. Why?

From: Ron (anonymous_at_discussions.microsoft.com)
Date: 02/29/04 

Date: Sun, 29 Feb 2004 10:56:07 -0800

The hard disk is not fragmented and is only about 10% full. Sometimes when deleting a file the hard disk light indicates activity for as long as 20-30 seconds. Other times the deletion is immediate. What is happening? Is it something to be concerned about? Is there anything I can do to eliminate the long deletion time?