"After 20 years working for a housing and social care agency in inner-city Birmingham, I joined the IPCC, as one of 18 new commissioners, with the aim of righting injustices. We claimed to be the most powerful civilian oversight body in the world, and we prepared to change the world. Five years on, I decided to leave. So what had gone wrong?"
I don't know. You were there for five years. You tell us.
Maybe having worked in housing and social care for 20 years meant the man was ill-equipped to do the job?
Or maybe you could read the rest of the article to which that is the opening paragraph. Y'know, kicking off a lengthy piece of writing with a question that you then go on to answer is a fairly standard rhetorical device.