/usr/local/bin/
Explanation
According to the Filesystem Hierarchy Standard (FHS), the /usr/local/ directory is for use by the system administrator when installing software locally. It needs to be safe from being overwritten when the system software is updated. The /usr/local/bin/ directory is for local binaries that are not managed by the distribution package manager. These binaries should be accessible to all users on the system. Therefore, binaries that have been compiled by the system administrator should be placed in /usr/local/bin/ to follow the FHS. References:
* Filesystem Hierarchy Standard - Linux Foundation
* Filesystem Hierarchy Standard (FHS) | Linux# - Geek University