For Santal, something started to kick in around modification number 93. I felt we had something there that had the potential to be powerful. Then I got lost in hundreds of other trials to realize that the theme we had in 93 was lost. We decided to throw away a year of work and start back from there. The solution was a few moves away, adding a 'key' that unlocked the whole formula. That key is the secret of Santal that prevents all the copies out there of it from achieving the same effect.
— Fabrice Penot talks about the creation of Santal 33. Read more at Le Labo's Founder Has Mixed Feelings About The Success Of Santal 33 at Fashionista.