Analysts do what they're asked to do. They are at the bottom of the Investment Banking hierarchy, which is very rigid. Like in the military, there is a chain of command that you need to fall into to be successful.

Analyst responsibilities can vary from running financial models or pitch books independently, to the most minuscule of duties including making copies and setting up conference calls. A typical day for a highly-sought analyst can be simply categorized as: doing whatever makes their Associate's/Vice President's/Managing Director's life easier.