I struggle a bit with this every day. All but 4 chickens free ranged when I took over their care. They had been free range for many years.
My preference would be to have fewer chickens and build a proper enclosure. I did suggest this at one point to the people who actually own the chickens. I drew up plans to enclose about three quarters of an acre of land which had bushes and trees established and was pretty much unused bar the occasional bit of half hearted vegetable growing. The objection wasn't even the cost. it was thought that such an enclosure would look unattractive.

We have other enclosures here for other animals; it seems these are not considered unattractive. I built these.

I was then left with trying to decide how best to try to ensure the chickens had what I considered a decent quality of life. For me, I know others see it differently for various reasons, 10 square feet per chicken in a run isn't satisfactory, particularity when there is no shortage of land. It was under these circumstances, and after reading lots and talking to other chicken keepers here that I decided on the multi coop system I have now.
I believe the chickens here have a good life. They have virtually unrestricted freedom, can choose who they live with and where. Despite encouraging them to use the coops at night I have had some roosting in trees for periods of time. They can breed, they get medical attention and food and my besotted type affection. I'm not sure if that last bit features in their life quality assessment

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However, much like humans, freedom means risk and like humans many don't make it to old age.