It would be helpful to define what type of website. I would expect personal blogs and corporate websites to have different lifespans
If you keep the domain renewed after the ICANN 10 year window, you're good. Over the years, and I'm online 20 years now, people just don't renew domains for multiple reasons. (e.g They diverted energy elsewhere or they have multiple domains to renew and can't afford to renew a particular domain, or the project had its moment in the sun and needs to die).