There was an issue with hibernate memory mapping that broke hibernate on my work Thinkpad for the first year or two that I had it.

Then at some point they fixed the issue, which if I remember correctly came down to "stop trying to be fancy and just do the straight-forward thing, which is correct". And since then I've had no issues.

I'm unclear why I had an issue with the Thinkpad but never had issues with any of the 5 or so Dell Inspirons I've had over the years.