During my final round case interview, after presenting my framework I was asked where I think the problem lied in a rising cost issue. After stating some areas in which costs may have risen, I was told that costs in all of these areas had remained the same. I then thought of a couple more costs which I was told were also the same. I then asked to see if competitors have also experienced this issue and was told they have. Next, I asked if customer preferences have changed and was told they have not, as well. After this, I asked if the airplane routes have changed and potentially incorporated international flights (the case was about per-flight rising costs within the airline industry) and was told the airline was domestic. Finally, I stated that this was an interesting problem (essentially admitting I was stuck) and was given the hint that "per hour" labor costs were the same which guided me to the correct conclusion that flights have been for longer distances recently. This whole process took around 3 minutes.
My question is if getting stuck in this fashion is detrimental towards my case performance. After receiving this insight, I successfully drove the case and arrived at the right answer, and my interviewer seemed fairly enthusiastic throughout the case. Additionally, I felt that the interviewer was withholding information she could have gave me (routes had changed, though were still domestic -- which I would have thought was a good enough insights to give me the next step).
Is this a bad mistake that may indicate I cannot successfully drive a case, or is this more in line with typical pressure testing? I know that it's difficult to arrive at a definitive answer with just my perspective, though would similar incidents be counted as substantial mistakes?
(edited)
