So many good people have left. Couple of reasons:
1) pay is seriously uncompetitive
2) promotion is arbitrary and you have to argue the toss for it. Unless you are in Manchester and went to the correct university and are friends with management.
3) they altered the consultant incentive scheme mid year with no consultation. The new scheme is confusing and not as generous
There is a transformation project which seems to have good aims but it means that there are more and more expensive change consultants cluttering up the top and it all has to be paid for with consultant sweat.
Some people seem arbitrarily lumbered with nothing but rubbish jobs for rubbish clients at rubbish day rates. These drag and get samey so you don’t learn much. Your fate depends on whether scheduling and management like you.