Always remember, no matter how frustated you are with your old job, Never, I repeat Never say anything ill about your previous company, boss, colleague or in general anything specific. Your best answer would be I’m looking to explore more into Insurance field (as WTW is into Insurance, likewise you could use any example for the company you are giving interview). You could say that (for any company) I have heard that Your company is employee driven and not just the work environment but also other facilities your company provide are upto the mark. Working in your company would be a pleasure for me and I’m sure there is so much more I could learn from your company.