We all know that companies use Leetcode problems for programming questions. But Facebook (and perhaps other big tech companies) also like to ask "system design and architecture" questions, which in my personal opinion don't have anything to do with the real world system design and architecture. Those questions are geared at recent college graduates who have no experience in system design. But if you've designed and created actual successful systems, you're likely to fail such questions. Because when you have real experience, you tend to know what works and what doesn't work in the real world, and you are likely to be conservative in the choice of your design techniques. However the interviewer expects you to use all kinds of design techniques which look good on the whiteboard but usually fail. I didn't realize how bad this situation was until I came across some books explaining how to "pass" these system design questions: you're basically supposed to say a load of bullshit, the more bullshit the better. I think the disconnect between the interview questions and the actual professional experience is simply stunning.