This question is especially important if you are applying for a management position.
An ideal answer will demonstrate that you are capable of assessing a situation and implementing improvements.
For example:
I started to notice that a lot of customers were complaining about feeling patronised by my agents. In response to this, I listened to the calls these complaints stemmed from and realised that words such as ‘wonderful’ were being over used.
I then had a meeting with the worst offenders in my team and suggested changes that they could make to correct this behaviour. After this meeting, customer complaints reduced and sales increased.