"Undesirable consequences" refers to negative or unfavorable outcomes that occur as a result of certain actions, decisions, or situations. Full definition
Similar and related words and phrases are presented below.
I am having more and more undesirable consequences of even fruit. (elanaspantry.com)
Without such an assessment, it is quite possible to produce unintended and undesirable consequences for the remaining species and cause more harm than good. (aspca.org)
It can also produce undesirable consequences, such as fear or aggression. (doglatindogtraining.com)