When my mother was pregnant with me in 1951 she was told that she would have to give up her grade four teaching job because it wasn't healthy for children to look at a pregnant woman. Today that would be considered absolutely ludicrous! In fact, now female teachers often show ultrasound pictures of her unborn child to their young students during class.
The union labour movement has drastically changed the policies that affect employees' hours of work, wages, environmental conditions and discipline. Collective bargaining, in fact, allows specific issues to be reviewed on a regular basis.
Usually policies are written in very clear and detailed language. Others, however, can be implied or even just assumed as being in place. There is a form of policy that the senior staff support which can only be explained as "this is how we've always done it".
Often policies are created in reaction to a problem that has occurred. For example, if staff is not dressing according to the expectations of the business owner, a business dress policy might be crafted and provided to all of the staff members who then would be expected to follow it.
Safety policies are usually written after an accident of some type has occurred and customer service policies can become necessary if enough complaints are received.
You see, the idea of having policies is so that there is a standard practice that can be understood and observed with the intent that doing this will be beneficial for the business and for the people involved. When policies are not effective or become out of date, however, they might actually do the opposite. Staff may resign, customers may go to another business for products and services and the business is subsequently hurt.
Often policies change because another business has been a leader in a specific area and the policies that they develop are then copied by other businesses. Sometimes politics motivate policy changes. Often significant changes are the result of grassroots movements where community groups or even staff members rally or advocate for a cause.
When businesses have policies that are set in concrete, there is little, if any room for flexibility or open-mindedness. Problems might not initially appear, but, over time, there will likely be discontent, anger or even resentment from people who are associated with the business who feel that there needs to be some changes which they think will be beneficial. And, as time goes on without any change occurring, the business will be hurt.
It is therefore important that businesses not only have policies but also be prepared to revise or add to them when they aren't as effective as they could be.