Their professional skills are not easily transferable, at least on the surface. They can't conceive of doing anything other than what they have been doing. They don't think about themselves in creative, innovative ways. They grew up with the myth of working for one company until retirement. Evaluating companies that are being merged, acquired, going bankrupt overnight.
Some executives sue their former companies simply because they are failing in their job search.
They are like a pro football team with only three plays. They need a coach, just like pro teams with complicated playbooks need a coach. Someone to help prioritize, to motivate, to assess progress, to set goals. Outplacement is the coach for the terminated executive. Helps people to see the part they played in their own downfall.