Yes, every soul reincarnates, but it does not happen in an absolute and continuous way.
If one is materialistic, has neglected spiritual practices to sustain one's soul (power meditation, yoga, etc.), or follows an ideology such as Buddhism, where the ultimate goal is spiritual suicide, then one will perish in every way and sense by the dissipation into the ether of the energies and elements that unite one's soul after death occurs.
However, on the other hand, new souls are still being created, thus increasing the population.
Death, the Afterlife and Hell
The Afterlife and Reincarnation [Fully Explained]