"What went wrong" is a phrase used to ask about the cause of a failure or problem. It means "why did this fail?" or "what caused this to be unsuccessful?". The phrase is often used to investigate the reasons behind a negative outcome or to identify mistakes that were made.

While "what went wrong" is the more common phrase, "what did go wrong" is also grammatically correct. However, the latter is generally used to emphasize the word "did" and is not as natural sounding as the former.

The phrase "go wrong" means to make a mistake or a bad decision. It can also refer to a situation where there are problems or things are not happening according to plan. Examples of using "go wrong" include "I followed the instructions to the letter and the computer still doesnt work. Where did I go wrong?" and "We have to figure out what went wrong with the experiment".