I don't think it's insecurity all the time, although I have run into people who refuse to trust an automated process because they can't see the work getting done...

I think a lot of resistance is due to, like others have said in this thread, unexpected incentives.

If someone's career progress, financial incentives, or work politics require the status quo, no changes will be welcome, and might even be perceived as an attack. (Yep, been there.)

If you miraculously can get the incentives changed, then you can make progress...