Change. It's a dirty word for some people. I mean it can be just rude. And even people who handle change well may find it rude to be faced with change when it occurs suddenly, without context or warning, creating a whiplash effect. This is particularly true if the people you are changing the rules on happen to be your clients.
In a world where so much happens online, change can and does happen quickly. There are many things that can change the dynamics of a team; some of them are out of our control. That's all the more reason to be particularly careful with the ones we do have control over, because when you have happy clients and staff, change may very well be seen as unwelcome and more restrictive.
Take changes in rules, for example. It's pretty safe to say those are likely to mean added restrictions; we are taking choices away from people. Or if we aren't a judge may be. And clients you are dealing with may be used to calling the shots, and would take particular offense when told they cannot do something. The same is true for staff, especially if they have become accustomed to doing it and are not given any reason for suddenly not being able to. And yet there are times when change is necessary, so what's the best way to do it?
With staff, involvement is particularly important, though you don't necessarily need consensus, nor is any explanation, "owed." Although that can go a long way, when that's not appropriate, at least provide a little context. Recognize that they may be used to a certain thing, and also let them know that changes are going to be made in the near future. Unless it's an issue relating to safety, trade secrets, or other high stake impact, there isn't a lot of need to impose changes suddenly and with no context. In fact, you have every reason to provide at least some context whenever possible.
One reason to provide at least some context is that it keeps people in the loop. This helps to maintain trust, improving or at least maintaining your relationship with key clients and employees.
Also, to the extent you provide context, they may be able to give feedback that could save time, money, and energy at the same time mistakes are prevented and an even better solution may become available.
And to the extent you provide the "policy consideration" behind the change, it will enable people to better comply with the changes.
This is also consistent with the fact that successful business owners say they stay in touch with customers and believe the real key to business success is employees. They are your greatest assets (and liabilities.) Treat them well.