“Career Suicide”, an over-used term I have heard in the past; it generally means that you have either made too many changes and/or joined multiple firms in your career, or you started and left a firm within a short period of time.
I can tell you without any hesitation this year 2019 no one is going to be subject to the “taint” of career suicide by making moves and retracting after finding out that maybe you moved too quickly or without enough due diligence on your part.