[CR]Why does "Buy it now" disappear?

(Example: Framebuilders:Alberto Masi)

Date: Sun, 24 Feb 2008 17:38:43 -0800
From: "Bob Freitas" <freitas1@pacbell.net>
To: CLASSIC RENDEZVOUS <classicrendezvous@bikelist.org>
Subject: [CR]Why does "Buy it now" disappear?

I notice sometimes the buy it now will disappear with the bid of a few dollars while other times it will stay til almost the end
                                    BOB FREITAS
                     MILL VALLEY, CA USA