I was in that space when I retired doing the financials and organization. It
Really works well if the company is willing to do the recommended changes. I have yet to see that. The first thing is generally to lay off the huge amount of duplicate employees in the company. In my case it was 24k people to be phased out over 5 years with hiring freezes in ever except sales.
The CEO said no way. Two years later they fired the CEO and then did exactly what was recommended. But that company was a mess and later got acquired and is no more. And yes the new acquiring company laid off all the people right at the start