It only falls if they don't take care of themselves. Look at Courtney Taylor, she's almost in her 40's and looks like she's still in her 20's, diet & exercise does wonders to the body when you age. Some women feel confident saying their real age while others probably have a bad self esteem issue.
Amber is letting herself go and probably has no plans on changing her diet/working out or enhancing herself again in the future, has a self esteem issue and probably got huge tits to make herself feel good, but now no longer does it, so insert the lies about age. She had so much potential but she failed lol