Oxidizing agents
The oxidation of an alcohol to form an aldehyde or ketone is very important in synthesis. In this process, the hydroxy hydrogen of the alcohol is replaced by a leaving group (X in the figure below).
Then, a base can abstract the proton bound to the alcohol carbon, which results in elimination of the X leaving group and formation of a new carbon-oxygen double bond. As you can see by looking closely at this general mechanism, tertiary alcohols cannot be oxidized in this way – there is no hydrogen to abstract in the final step!