I've written before that every decision involves a trade-off. When considering the trade-offs that every decision requires, you should also keep in mind any unintended consequences that the decision may create. Consider the following example:

A client of mine recently changed AMSes. As part of that change, members have to log in to the website using a unique email address. (Previously members had used their last name and their member ID.) The challenge is that the association has thousands of member records without email addresses and as a result, a member without an email address cannot login to the website without contacting the association directly and speaking with a staff person (i.e., there is not automated way for the member to retrieve a username/password reset via email).

So the unintended consequence of this decision was that the staff now has to manage dozens of customer service calls to help members login for the first time, something they had not planned for.

Could this additional work been avoided via some other login method? Maybe. Or maybe not. But a discussion needed to happen, so that the association could make a fully-informed decision and understand the ramifications (i.e., the trade-offs and the potential unintended consequences) of their decisions.

So as you make any decision, ask yourself: "Could this decision create any unintended consequences?"