Why is oil maintenance in today's environment so essential?

The modern engine with all the EPA requirements must run clean for longer periods of time so the build up of carbons within the oil must be kept to a minimum to meet
these environmental demands. Fine tolerances in hydraulic circuitry call for much cleaner
oil than before, to get optimum working performance from our systems.
To achieve this much required cleaner oil, we need to look closely at oil maintenance.
However, before we do this, lets take a look at lubricating oil.