@meso It allows easily maximizing the engine's compression ratio and car manufacturer's really consider it good if years down the line a timing belt or chain snaps and it's time to buy expensive parts, or a new engine, or a new car.

It isn't much of a problem if there's a timing chain - as the chain tends to start rattling prior to failure and therefore allows for replacement before it fails.

There's a problem with timing belts, as they do not rattle and break without warning at end of life (and of course the belt is usually deep within the engine and a pain in the ass to replace too).

Some cars now combine an interference engine with a oil-lubricated timing belt (for a 1% fuel efficiency improvement) - as expected, the result is that the timing belt can snap prior to the recommended replacement interval, as shockingly oil attacks and degrades rubber (even if it's PTFE coated).