Linux

How long have you been using it, and on how many computers?

From the Arch wiki:

Before upgrading, users are expected to visit the Arch Linux home page to check the latest news, or alternatively subscribe to the RSS feed or the arch-announce mailing list. When updates require out-of-the-ordinary user intervention (more than what can be handled simply by following the instructions given by pacman), an appropriate news post will be made.

Before upgrading fundamental software (such as the kernel, xorg, systemd, or glibc) to a new version, look over the appropriate forum to see if there have been any reported problems.

Users must equally be aware that upgrading packages can raise unexpected problems that could need immediate intervention; therefore, it is discouraged to upgrade a stable system shortly before it is required for carrying out an important task. Instead, wait to upgrade until there is enough time available to resolve any post-upgrade issues.

So unless Endeavour devs are doing anything special to make sure you can safely upgrade without checking the Arch news (and AFAIK, they don't, like most Arch based distros), you should probably check it. Of course it's a matter of chance if your system is the one that gets hit by some bug or conflict, YMMV, but eventually you'd hit a snag if you ignore Arch's devs advice.