This album also features two tracks that were never released as singles ("A Song for ××" and "Who..."). Due to the large number of Ayumi Hamasaki singles, the songs on the album are fan favorites. Songs from her debut album such as "A Song for ××", "Trust", and "Depend on You" were re-recorded, showing the changes in Hamasaki's vocal qualities. The initial pressings had six different variations that each came with its own "gift".
A Best was released simultaneously with Utada Hikaru's Distance, which topped the charts on the initial week of release with 3,002,720 copies in its first week; A Best debuted at number two with 2,874,870 copies. Additionally, it topped the charts the second week of its release and is the sixth highest-selling album of all time in Japan. To date A BEST is Ayumi Hamasaki's highest selling album in Japan. It sold 4,301,353 copies total in Japan and 6,700,000 copies in Asia.
Though this was her best selling album, Hamasaki opposed it publicly, stating: "It was too early for release."
According to Oricon, A Best is the second highest selling Japanese album of the decade.
