Matte lipstick is specifically formulated to look unshiny. The finish is intended to be dull/blunt…devoid of moisture, similar to what face powder accomplishes for a shiny complexion.
Until its introduction in the 90s all mainstream lip makeup formulations shared the common feature of moisture, some shinier, some glossier, some richer in texture but all somewhat “creamy.” Trend seekers and makeup lovers did like the idea of an anti-norm, no-shimmer, non-lustrous pout but the formulations were so very dry that they were uncomfortable wear. Since then there have been some technical advances allowing for the dry look without the unpleasant feel. And because of the lack of oils, matte lipstick is generally much longer lasting than the more traditional predecessors which wear, wipe or transfer off relatively quickly.