As no one seems to have explicitly mentioned it yet, I'm going to point out what the word stable means in the context of software releases.
All it means is that that particular release has no bugs which weren't in the previous release (called regressions), excluding bugs which are only within new features.
If a piece of software has a 3.0 release with 1,000 bugs and is so buggy that it's useless, but the latest development builds have fixed all of these and added one new one, the development builds aren't stable because of that one new bug. If a different piece of software has a 7.0 release and it's got a tiny number of bugs, but the development builds include a new feature, and that new feature has thousands of bugs and is completely unusable, but all bugs apply only to the new feature, the development builds can be considered candidates for a stable release.
Stable doesn't necessarily mean better. The point of software releases being stable is that if you use the software to do something and it works, upgrading to the next stable release won't make the thing you do stop working.
As a Dolphin-based example, let's say some hypothetical game boots into the menu perfectly, but when you actually try to start a new game or load an existing save, it crashes. If a build comes along later that means you can start a new game and load a save, then most people would prefer it, but if it made the colours in the menu look wrong, it couldn't be considered as a candidate for a stable release. If a user liked booting into the game's menu and taking screenshots of the animation in the background, though, they might prefer the older build where only the menu works, so they wouldn't want to upgrade even though loads of other people would.
All it means is that that particular release has no bugs which weren't in the previous release (called regressions), excluding bugs which are only within new features.
If a piece of software has a 3.0 release with 1,000 bugs and is so buggy that it's useless, but the latest development builds have fixed all of these and added one new one, the development builds aren't stable because of that one new bug. If a different piece of software has a 7.0 release and it's got a tiny number of bugs, but the development builds include a new feature, and that new feature has thousands of bugs and is completely unusable, but all bugs apply only to the new feature, the development builds can be considered candidates for a stable release.
Stable doesn't necessarily mean better. The point of software releases being stable is that if you use the software to do something and it works, upgrading to the next stable release won't make the thing you do stop working.
As a Dolphin-based example, let's say some hypothetical game boots into the menu perfectly, but when you actually try to start a new game or load an existing save, it crashes. If a build comes along later that means you can start a new game and load a save, then most people would prefer it, but if it made the colours in the menu look wrong, it couldn't be considered as a candidate for a stable release. If a user liked booting into the game's menu and taking screenshots of the animation in the background, though, they might prefer the older build where only the menu works, so they wouldn't want to upgrade even though loads of other people would.
OS: Windows 10 64 bit Professional
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56