Command blocks may not work or will only sometimes work, depending on where it is in the world.

Whenever using the execute command, the command block will only sometimes run properly (a command block that works will not work in a different spot) this is obviously an issue if you want to use command blocks as finding those spots that work is annoying and there is no reason it should be that way. quick demo: https://youtu.be/DxVKCQtURvc