Probably for the same reason clients use PA. They can appear superficially competent and straightforward, especially with the emphasis on execution not just strategy. I'll be honest when I was with them I did no public sector work, worked purely with global organisations outside of the UK, and one of my biggest assignments was clearing up a McKinsey inspired mess. I joined PA because I had been in a specialist boutique consultancy and wanted to find out if a big firm had an operating model that was less seat of the pants. They didn't.It was also the most miserable time of my life because of how we (and the clients) were treated. Some PA people who post here seem to think it is only the deadwood who leave. Far from it, it is usually those who have swallowed the red pill, including the only two partners I respected in my practice.And post PA I earn a lot more, work less, enjoy life more, see my wife and children and do work that I value.Don't get me wrong, PA does do some good work, and it suits some people especially those who have come up through the ranks or are in a niche sector,but the day I left 123 for the last time was simply wonderful.