I found the reason!!! well at least in my speculation...and I think it's VERY good to the music video...
She has said herself that there is TWO DIFFERENT AYUs...One Ayumi a product of Avex, the other Ayumi, herself...the real her, who and what she is to her relatives.
The robot, aka the product of avex, sings etc...when she creates HERSELF that is the other ayumi, the real her hence 'real me' she dances etc just to entertain the video...*=thought= ayu might really like to dance in her home life* just like Fly High she was singing on the stage and is also, in the crowd. There is one Ayu, the Ayu named Ayumi Hamasaki a product of Avex the Singer-Queen Cyborg Factory. There is the second Ayu, the Ayu named 'ayu' to her folks at home, this is her in white...At the end 'ayu' is thrown away because now Ayumi Hamasaki is a product...she throws her real self away...for her fans...
*I think that was thoughful enough , -tear jerk- lol
edit: forgot to read the other posts
I don't believe the Q-Ayu is thrown away...this is due to because she puts the card in the slot to MAKE the real me ayu...for all those who don't think I'm right watch it again it goes in and then it makes the white ayu
