It depends. Most likely the interviewer would like to know the comparative analysis among similar kind of BI tools. If you have worked in Cognos BI or In Hyperion or something like that you might answer that from experience. If not, then you can point out some basics like:
- It is simply a reporting & analysis tool that does not allow WRITE BACK to database.
- It's in-built reporting-printing is not very efficient (some third party tool like N-Printing is used)
People might mention some more to add.
Here is a link that discusses about the same which I do not agree for all points in that sense.
Many interview questions are "open-ended", that is there is no right or wrong answer. It is rather about your opinion. For example, QlikView has only 13 types of charts. Is it a "limitation"? Technically speaking - yes, because it is a fixed number. Even if there were 13 million types, it would be a "limitation". On the other hand, the often used charts are line, bar, combo, gauge, scatter, pivot, and straight tables - only seven. So, 13 may be not an actual limitation...
I am agree with the poor reporting engine, I would also say that QV is limited in terms of how much data you can allocate in RAM. About scalability, I've heard some opinions about being a limitation in QlikView, but is it really a limitation or disadvantage in QV?