If for instance you consider anything that can be legally and uniterraly taken away from you as not owned, that definition becomes really really small, short of you being a diplomat or some special entity.
Many see "owning" things in a more colloquial way, but that's also how Amazon gets by with their shenanigans, as it still feels like ownership day to day.
As sister comment points out, civil forfeiture is one. Your car being involved in a criminal investigation and getting saved for perpetuity as evidence would be another.
Funnier examples: let's say it's a self driving car, as you proudly admire your brand new car delivered car, firmware is overwritten by error and is sent to another home, who also closes the delivery. Factory management software is buggy as hell and your car got reassigned some random info of another lost car, but marked as delivered to you anyway, so the burden of proof is now on your side.
You might be fighting that car maker in court for the rest of your life without ever seeing any compensation or getting back "your" car.
> mortgaged home
If it's mortgaged it's just not yours in the first place. I'm sure you have clauses in your loan contract detailing how the loaner can unilateraly decide that circumstances changed, you're now too much of a risk, and request near inmediate full repay of the rest of loan or else they liquidate the property.
Land laws have also their funnier clauses, where someone squatting your property for a decade can request legal ownership, depending on the local arrangements.