This question helps the interviewer assess your level of self-awareness and whether you're open and honest about your shortcomings. Pick a weakness that is not a core skill for this position. Frame your greatest weakness as an asset in its own right. Being a perfectionist can be a weakness. A well-intentioned shortcoming or a growth opportunity you've self-identified that is integral to your career goals would be a good example. Recognizing that you aren't great at something and acknowledging you identify it as a growth opportunity is a good start.