Conan O'Brien has probably had the most unusual career trajectory of any current late-night host. When he joined NBC's Late Night in 1993, replacing David Letterman, he had virtually no on-air experience. He did, however, have comedy-writing chops: O'Brien edited the humor magazine The Harvard Lampoon as a student, then wrote for Saturday Night Live and was a writer and producer for The Simpsons.
Although it took him a while to get comfortable in front of the camera — many critics initially gave him bad reviews — he eventually did so well on Late Night that he became the host of The Tonight Show in 2009, after Jay Leno's ill-fated move to prime time. But that arrangement was short-lived: Leno's show was canceled, the host moved back to Tonight, and O'Brien eventually landed at TBS in the 11 p.m. slot.
O'Brien spoke with Fresh Air's Terry Gross in 2003, a few days before a special broadcast celebrating his 10th anniversary at Late Night.