Ultimately he is responsible for his own safety so long as you are providing a safe dwelling; however, if he is endangering others you have a couple remedies as I see it.

Similar theme being, if the people can't figure out simple economics, the government will need to protect us from endangering ourselves. 

There are also lots that are unbuildable because they are in "Scrub Jay" habitats (a small endangered bird).

My lease does state - "Will Conduct themselves and require other persons on the property with Tenant’s consent to conduct themselves not to disturb, annoy, endanger, or interfere with their neighbor’s peaceful enjoyment of the property. " & "Will not Disturb the peace and quiet of other tenants or neighbors.

At one point, two of the caps blew off and into the alley below endangering the general public.

Was it a crime such as embezzlement or tax evasion that did not endanger a person?

With a real estate professional, at least you are assured of some level of instruction in the subject matter and a license (which exists to protect consumers).And if you can find a lazy appraiser in the era of TRID, take a picture, as that is an endangered species nearing extinction.

Arborist whatever, if it falls it can endanger people. 

You want to "control everything, own nothing" so as to be as unattractive a lawsuit target as possible.You want to assure that a lawsuit from one property will not endanger others, or at least not a "large" portfolio of smaller properties.You want emplace a layer of protection between your entity structure and yourself personally.

Small motel and bed-and-breakfast operators complain that the business model endangers their survival.""