He that stumbles twice over the same stone, deserves to break his shins.

The saying warns that a person should learn from an earlier mistake. Repeating the same error is treated not as bad luck but as a failure to notice, remember, or act on a lesson already made clear by experience.

The repeated stumble represents making the same mistake again. The saying's harsh language blames the person for failing to learn and presents the resulting pain as a consequence they should have avoided.

Use it to criticize someone who repeats an avoidable mistake after having already experienced its harmful consequences. Its deliberately severe wording suits a blunt judgment, rather than sympathetic advice to someone facing a new or unavoidable difficulty.