MO was not a successful lawyer. She received a law degree, but didn't do much with it. She was what was known in Chicago as a "Jesse Hire". An "untouchable hire", meaning this is someone on the City payroll who can never be fired or even disciplined in any way because their employment was a political favor to someone. These types of hires weren't expected to do much...read magazines all day, take a few lunch breaks, etc. She actually hated being a lawyer.
Then a fellow "Jesse hire" Valerie Jarrett took her over to the U of C Medical Center to "work." They wanted Barry's wife on the payroll so that they could funnel money to him through her as rewards for steering legislation towards passage that would benefit U of C. This is how Chicago works.
Michelle didn’t do any more work at the Medical Center than she did for the City and her job duties involved trying to keep black people from going to the emergency room at the hospital for treatment without insurance and instead go to these sub-par "medical clinics" that the Medical Center wanted them steered towards instead. At one point, Michelle received a ridiculously large raise right around the time that the U of C received a massive funding infusion for the Medical Center from Springfield, where Barry was on his way to becoming a United States Senator. Surely this was just a coincidence and was not a way for U of C to buy favor from the next US Senator representing Illinois by dramatically increasing his wife’s pay to over $300,000/year for doing relatively nothing all day...um hmm.
After Michelle vacated her position in 2007 to join the Obama presidential campaign full-time the Medical Center did not bother replacing her and eventually eliminated her old job since there was no need for this position or the expenditure as it was only there in the first place to buy influence from Michelle’s husband.