When do you get best feedback ever?

Based on my experience, it is the day when you’re leaving company.

I have seen people leaving who were begged to stay, offered anything.
People who were announced as “regretted loss” for company.
People for whom parties were organised by co-workers and companies
to show appreciation for what they have done for them.
I have seen people crying at the announcements that some people are leaving.

I have also seen people leaving without a trace.
Nobody mentioned them the day after.
Nobody organised parties and nobody stayed in touch.
Nobody tried to talk them out of it.

Very strong and very honest feedback like that you will get only when you’re leaving.
Nobody has any hidden interests, no more games to play.

What would you prefer? How was it when you were leaving?