Not necessarily. There is a point where oil manufacturers follow"more is better". Never found out why, even when speaking to formulators. X amount of ZDDP is needed in motor oil. Some blends put in too much and eventually separates outs and becomes an ingredient of sludge. ZDDP is that wonder drug that is very important in motor oil. Brad Penn or Penn 1 hangs around on every moving part of an engine. Your car gets started in maybe 2,3,4 weeks.That,call it sticky or gooey, keeps all the internal parts from being worn on the start up. Seen that that at salvage yards when pulling parts. Modern cars, with low levels of ZDDP, maybe sitting a year or 2 or 3 have the faintest of lubrication on the internal parts. Are the motors clean? YES. They have more dry start wear. When you find a sludge bucket, they are a greasy mess and the parts are all coated( accounting for good service). Good maintenance programs are a definite plus and so is ZDDP fortified oil