Amish communities vary wildly on what is acceptable from community to community which can include trivial things like colors and cuts of garments, phone usage/l

Amish communities vary wildly on what is acceptable from community to community which can include trivial things like colors and cuts of garments, phone usage/location, type of carriage/buggy features, and what level of mechanization is tolerated. It rarely has a logical reason beyond "this is the way" and is generally dictated by the elders of that specific community. The differences also extend to things like the conditions they'll let a member formerly in good standing return and courtship customs. If you read Ira Wagler's book Growing Up Amish, he covers some of this as his family (and him alone) moved around various Amish communities in North America.