What happens when you shut down a product (with life time buyers)?

Hi everybody!

Have you ever shut down a website/business where people bought life time service?

I DON'T have this kind of problem (at least not right now), I am just wondering.

Do you just notify these users and maybe run the service/website for a few months before shutting down completely?

The reason could be: not worth the time; not profitable; got burnt out.

What do you think about this situation?