A tell tale sign of a good boss is someone who has good communication skills, as well as the ability to listen and understand what is being discussed, not just "hear" it.  Some bosses, however, are just power-hungry and think they are always right and can make often ridiculous demands of employees.

An incompetent boss (both with schedules and people skills) tries to coarse an employee to work a few extra days after his last day, even though he is literally moving out of town.