There’s plenty of Unreleased 11/10s, most we will never hear because they are kept better under lock… but also we have varying tastes so an 11/10 for you might be a 1/10 for me and vice versa.
A few unreleased songs I would give 11/10s have thankfully seen a release like the songs on The Lost Tapes by the Sugababes, and “Just Can’t Give You Up” by Dannii Minogue. Still unreleased, I’d say Roisin’s cover of “Slave To Love” is an 11, Sophie EB’s “Work It Out”, Girls Can’t Catch’s “Alone” (and their cover of “L.E.S. Artistes” dddd), and Kylie’s “Sexual Gold” and “(Everything) I Know”.