As with any open source software, anyone can download MySQL sources, build binaries for some platforms and distribute their own packages. So we have the official ones from Oracle, MariaDB, and Percona - the makers of MySQL and its forks respectively. There are also those distributed with operating systems or that are available for install from their standard repositories. Some people or groups also create packages out of the most recent versions of various software and make them available to the world. Finally, some mash up a vanilla MySQL with various patches creating even more options. What to choose?
Database is a piece of software that needs to be reliable in every way. It often holds the only complete and up-to-date copy of data. It may keep confidential information. It may be supporting an application where every minute of downtime costs a little fortune. Or perhaps it just needs to be as efficient as it can possibly be. There could be many more reasons for which it is not just like any other software.
Another aspect are package upgrades. Perhaps the most annoying thing about MySQL from various Linux distributions is that upgrade options are typically limited, if possible at all. Either you are stuck on a single major version or you may not be even seeing many minor releases. At the same time a server, once installed, may need to work several years, which could be enough time for two or three MySQL generations.
For all these reasons it is good to choose reliable packages. The packages distributed by the respective vendors – Oracle, Percona, or MariaDB. They guarantee that MySQL binaries are built correctly - in a controlled environment and with proper build options. But what may be even more important, only such binaries offer the maximum reliability as they undergo proper testing every time before being actually released. Using their packages also enables easy upgrades to any future versions of MySQL.
Of course, if you are after a set of features that does not exist in any single official distribution, you may have little choice but to rely on a third-party build.