Depending on the firm, what the question was, and how badly you messed it up.I messed up one question in my TC interview, would you say that will ruin my chances at getting the opportunity? Hate this :/
If it makes you feel better, I also messed up a few questions during my AC and this was confirmed in my post-AC feedback, where the grad recruiter listed some questions that I also felt like I had answered badly. However, I still passed the AC which just goes to show that firms hardly expect perfection.