"To know the consequences" means to have an understanding of the results or outcomes that may occur as a result of certain actions or decisions you make. Full definition
For example, scientists don't know the consequences of putting aerosols into the upper atmosphere. (sciencenewsforstudents.org)
Your child should generally know the consequences for breaking certain rules, but effective discipline isn't a black - and - white affair. (verywellfamily.com)
As long as people know the consequences, they can have a drink every now and then but shouldn't make it a habit. (KetoDietApp.com)