Why the drain keeps coming back
Grease and fat, food and organic waste, scale, sludge and mineral deposits do not leave a pipe when a snake punches through them. They line the wall and narrow the bore a little more every month, until the drain backs up again and the cycle repeats. Tree roots and the debris left behind after rooter service make it worse.
That is why jetting suits recurring drains, backups and older plumbing. The line is often not blocked in one spot, it is dirty along its whole length.
