Elizabeth Warren - Election vs. Selection

There is a huge debate about what prevents US president Obama from nominating Dr. Elizabeth Warren, the Harvard Law professor to head the Bureau of Consumer Financial Protection Agency. Recently Fortune asks the question in an article titled Why not Elizabeth Warren for BCFP? The Warren episode exposes a fundamental political problem of election vs. selection. Political parties prefer voters and population in general to "select" one candidate.

Difference between Selection and Electiondiv