One of the reasons why Michigan has switched to Eastern central time is they are always on central daylight time. They are exempted from daylight saving time. Some people are confused because not all of Michigan is in the Eastern Time Zone so it can be a bit confusing when you do not know where you are in Michigan exactly.
If there would be a daylight saving time, this means that the area is going to have double daylight which is not really needed at this point in time. The timezone has helped other people do the different activities that they have always wanted. There are still other people who are pro daylight saving time.
Most of Michigan is in the Eastern Time Zone excepting four counties. These four counties are Gogebic, Iron, Dickinson, and Menominee. These four counties are in the Central Time Zone. Due to daylight savings time the fact that most of Michigan is in the Eastern Time Zone means that most people in Michigan enjoy very long summer days with dayight that lasts until 9 or even 10 pm.
The reasoning for this is simple. The way the timezones used to fall meant that back around the turn of the century the sun was setting around 7pm in July in Detroit. The people wanted to be able to enjoy the summer days more so the timezone was changed to accomodate this.