Blizzard's recent games sometimes feel like elaborate slot machines. Overwatch's loot boxes and Hearthstone's card packs, both of which can be purchased or earned by leveling up, randomly dole out new cosmetic options (Overwatch) or cards (Hearthstone) when they're opened. Perhaps the biggest problem with this system is the frequency with which you receive duplicate items instead of getting something new. Blizzard announced that it's addressing that issue by giving out fewer duplicate items in Overwatch and more Legendary-tier cards in Hearthstone.
These random item generators effectively train Overwatch and Hearthstone players to give Blizzard more and more money in exchange for the chance to get the items they want. You can't directly purchase a specific skin, voice line, or card--you have to receive them from a loot box or card pack. The only exceptions are the ability to spend "credits" earned from loot boxes or duplicate items to buy stuff in Overwatch and "dusting" cards to make other cards in Hearthstone. That system only works if it feels good, so these changes make sense.
You can glean as much from the Overwatch patch notes discussing the change:
We always want the experience of opening an in-game loot box to feel exciting and rewarding, and in our latest patch we’re working to improve that experience in two key ways. First, we’re drastically reducing the amount of duplicates players will receive when opening loot boxes. Second, to compensate for this reduction of duplicate items, we’re also increasing the overall amount of credits players will receive from loot boxes. On average, players should be earning just as many credits, if not slightly more, from loot boxes than they did prior to these changes.
Similar language is used in the forum post about Hearthstone's card pack changes. Hearthstone community manager Keganbe said that "having fun and exciting moments" is important to the game's developers, especially when it comes to "cracking open" card packs. To achieve that goal, Blizzard now guarantees that you will get a Legendary card within the first 10 packs you open from a specific set, that you won't receive duplicate Legendary cards, and that you won't receive more cards in a pack than you can use in a deck. This should give you a wider variety of cards.
Both of these changes have a clear goal: making sure people continue to buy loot boxes and card packs. That's how Overwatch and Hearthstone are monetized--the former costs $40 upfront, but it doesn't have any recurring fees, and Blizzard doesn't charge for new maps or heroes. The latter is initially free-to-play, but new heroes and "journeys" have to be purchased separately. Maintaining the servers, releasing updates, and simply making a profit requires Blizzard to find other monetization tools. Loot boxes and card packs appear to be doing the job pretty well so far.
Re-balanced loot boxes aren't the only changes heading to Overwatch. The game will also receive an improved Highlights feature that makes it easier to save good plays for later viewing. Now you'll be able to record a Highlight by pressing a single button. Overwatch will then record your gameplay, store it in a "Recently Captured" section of the Highlights menu, and save it using your console or PC's video tools. The game will also automatically record up to five Highlights (just like it does now) when it thinks you're doing particularly well.
You can test the new Highlights--and other changes, such as the ability to make custom reticles--on the Public Test Region server.