because people are self serving, its human nature in man, man will to as little to nothing if he is able to get a share.
people will only bear the burden of other people for a short time as noted by my link to the pilgrims.
from my link.....
The Pilgrims started out with communal property rules. When they first settled at Plymouth, they were told: "Share everything, share the work, and we'll share the harvest."
The colony's contract said their new settlement was to be a "common." Everyone was to receive necessities out of the common stock. There was to be little individual property.
That wasn't the only thing about the Plymouth Colony that sounds like it was from Karl Marx: Its labor was to be organized according to the different capabilities of the settlers. People would produce according to their abilities and consume according to their needs. That sure sounds fair.
They nearly starved and created what economists call the "tragedy of the commons."
If people can access the same stuff by working less, they will. Plymouth settlers faked illness instead of working the common property. The harvest was meager, and for two years, there was famine. But then, after the colony's governor, William Bradford, wrote that they should "set corn every man for his own particular," they dropped the commons idea. He assigned to every family a parcel of land to treat as its own.