Apple has proudly touted its trade-in and recycling programs, mentioning them prominently at major events, during investor calls, and on its website. But in changes that quietly went into effect this week, the company reduced the trade-in value for many of its products, meaning consumers will get less money for their old iPhones and other devices than they did previously.

MacRumors reported the news based on looking at values estimated on Apple's online store before and after the change, and the site listed the tracked changes. Trading in an iPhone XS Max was previously estimated to fetch the consumer $600 toward an upgrade, but that number is now $500. The iPhone 8 estimate has gone down from $220 to $180, an iPad Air from $100 to $70, and an Apple Watch series 4 went from $110 to $100.

It's interesting to note, however, that Mac trade-in values were barely affected, if they changed at all. And all Apple Watch models except the newest series 4 model also remained the same. It's mainly the iPhone and iPad product lines that have been impacted.

Apple hasn't publicly stated why it made these changes, but it could be some combination of device value depreciation and efforts to improve profit margins as much as possible.

iPhone revenue has been slow to move in recent quarters, so any bit might help, though Apple has mostly made up for those losses with its rapidly growing services and wearables businesses. For example, Apple sold $6 billion worth of AirPods in 2019, according to market researchers, and a recent report estimated that the AirPods business alone is worth more than Nvidia, Adobe, or AMD individually, and only slightly less than all of Uber.

As is often the case with valuable assets like cars and electronics, consumers will generally get better deals selling their old iPhones and iPads to private buyers than they would through the trade-in program. These changes may serve as a reminder about that, though of course these products will depreciate in that channel as well.

On the other hand, Apple's trade-in program funnels the devices into a system that the company claims ensures efficient recycling of devices that are no longer viable.