What is the endgame for a Telvanni wizard (in-lore)?

Sorry if this is an obvious question. I do really like the scheming and power hungriness of a House Telvanni wizard. Climbing through the ranks in House Telvanni is definitely the most fun. However, what does a Telvanni wizard expect to find when they reach their desired rank? When they become a Magister or something, do all they do is study magic all day? Most Telvannis don't seem interested in governing or politics anyway, so what are they interested in?