Does anyone else have trouble working out their palate?

When I try a gl of Jack Daniels, and a gl of Jim Bean, blindfolded for instance; I still can't work out the difference in taste, or which is which. Same with a gl of Merlot, and a gl of Syrah,or if I am given a gl of German lager and a gl of Czech lager. Yet I've been drinking all this stuff for years!