I feel an interviewer would like to hear something positive about change, and your attitude towards change shows a lot about your personality. We all know that it is metamorphosis that ultimately makes a butterfly out of a caterpillar. So, change for something you believe in and stand steadfast in would be welcomed by most employers as it is a positive sign.
By asking why you are changing, the employer wants to know your attitude towards change, so you let them know why you are changing your current job.
The follow-up question is normally - why did you not see this change when you joined the earlier organization? This could be handled by the different things you learned in the current organization, which gave way to the present change.
Don't attribute any negative reasons for your change, e.g., "I don't like my previous boss or team member," etc.
Best wishes, Ajeet, for a wonderful career ahead.
Regards,
Joseph Puthur - Trainer at TrainingGuru.co.in