Ethylene gas in biology, is known as a hormone. Hormones, as they do in humans, cause growth. Producers of produce use a process that they "gas blast" the fruit or veggies to have them mature faster so they can go to resale faster. Produce that is exposed to ethylene gas isn't as flavorful, but they do make a quick alternative to slow ripening.
Ethylene gas does not take away flavor, but actually adds flavor by breaking down starch into sugar using the enzyme alpha-amylase. This is the reason why produce markets use ethylene to ripen fruit when they arrive so the fruit can obtain their flavor when they hit the shelves. If ripening occurs naturally, fruits would sit on the shelf longer, and in the business world that hurts the inventory turnover rate. Ethylene causes fruit to RIPEN faster, spoiling occurs at the end of the ripening process.