Can anyone share recent experiences / stories on Cloud repatriation projects

I'd like to increase my awareness of current trends in bringing services back in-house through so-called Cloud Repatriation or Reverse Cloud Migration.

Can anyone share any war stories (as specific or generalized as appropriate) on current or recent projects.

Any wise words? Any estimates of the impact on service costs, blockers, unintended consequences significant wins etc.

Any links to worth-reading articles?

Thanks