It is important to change plans, when things change that make your previous plans bad.
Imagine that you own a business. You have carefully surveyed the business environment and made plans to expand into a new product area: widgets. You have written up all the necessary documentation and spoken to investors about obtaining the capital needed for this new venture. You have started looking for a site for a new widget factory.
The specific change does not matter. What matters is that something has changed and you, as a smart business owner, now need to rethink whether you want to follow through on your previous plans and get into the business of selling widgets.
All this decision-making is obvious in a business context. It should just as obvious in an estate planning context. You need to change plans when the environment changes, as the Herald News points out in "Revisiting Your Plan."
Like the business environment, the estate planning environment is constantly changing. There are laws that could possibly have an impact on your estate change. Your goals and life circumstances also change. It would be as ridiculous to not change your estate plan when these changes happen, as it would be to not change a business plan when the business environment changes.
Make sure that you keep in contact with an estate planning attorney, who can let you know if anything has changed in a way that should necessitate changing your estate plan.
Reference: Herald News (April 22, 2018) "Revisiting Your Plan."